diff --git a/config/alfresco/subsystems/Search/solr/solr-search-context.xml b/config/alfresco/subsystems/Search/solr/solr-search-context.xml
index dc82848a2a..b6c54bdf2d 100644
--- a/config/alfresco/subsystems/Search/solr/solr-search-context.xml
+++ b/config/alfresco/subsystems/Search/solr/solr-search-context.xml
@@ -40,6 +40,9 @@
         <property name="permissionService">
             <ref bean="permissionService" />
         </property>
+        <property name="tenantService">
+            <ref bean="tenantService" />
+        </property>
         <property name="languageMappings">
             <map>
                 <entry key="lucene" value="alfresco" />
@@ -164,9 +167,6 @@
         <property name="nodeService">
             <ref bean="mlAwareNodeService" />
         </property>
-        <property name="tenantService">
-            <ref bean="tenantService"/>
-        </property>
         <property name="dictionaryService">
             <ref bean="dictionaryService" />
         </property>
diff --git a/source/java/org/alfresco/cmis/search/CmisFunctionEvaluationContext.java b/source/java/org/alfresco/cmis/search/CmisFunctionEvaluationContext.java
index ec61ad212c..762631f274 100644
--- a/source/java/org/alfresco/cmis/search/CmisFunctionEvaluationContext.java
+++ b/source/java/org/alfresco/cmis/search/CmisFunctionEvaluationContext.java
@@ -93,6 +93,7 @@ public class CmisFunctionEvaluationContext implements FunctionEvaluationContext
         EXPOSED_FIELDS.add(AbstractLuceneQueryParser.FIELD_PRIMARYASSOCTYPEQNAME);
         EXPOSED_FIELDS.add(AbstractLuceneQueryParser.FIELD_DBID);
         EXPOSED_FIELDS.add(AbstractLuceneQueryParser.FIELD_TAG);
+        EXPOSED_FIELDS.add(AbstractLuceneQueryParser.FIELD_TENANT);
         EXPOSED_FIELDS.add(AbstractLuceneQueryParser.FIELD_ANCESTOR);
         
         
diff --git a/source/java/org/alfresco/repo/search/impl/solr/SolrIndexerAndSearcherFactory.java b/source/java/org/alfresco/repo/search/impl/solr/SolrIndexerAndSearcherFactory.java
index 9642d70cc5..f883779269 100644
--- a/source/java/org/alfresco/repo/search/impl/solr/SolrIndexerAndSearcherFactory.java
+++ b/source/java/org/alfresco/repo/search/impl/solr/SolrIndexerAndSearcherFactory.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005-2010 Alfresco Software Limited.
+ * Copyright (C) 2005-2011 Alfresco Software Limited.
  *
  * This file is part of Alfresco
  *
@@ -23,9 +23,7 @@ import org.alfresco.repo.search.IndexerException;
 import org.alfresco.repo.search.QueryRegisterComponent;
 import org.alfresco.repo.search.SearcherException;
 import org.alfresco.repo.search.impl.NoActionIndexer;
-import org.alfresco.repo.search.impl.lucene.ADMLuceneSearcherImpl;
 import org.alfresco.repo.search.impl.lucene.AbstractIndexerAndSearcher;
-import org.alfresco.repo.tenant.TenantService;
 import org.alfresco.service.cmr.dictionary.DictionaryService;
 import org.alfresco.service.cmr.repository.NodeService;
 import org.alfresco.service.cmr.repository.StoreRef;
@@ -43,7 +41,6 @@ public class SolrIndexerAndSearcherFactory extends AbstractIndexerAndSearcher
     private NamespacePrefixResolver namespacePrefixResolver;
     private NodeService nodeService;
     private QueryRegisterComponent queryRegister;
-    private TenantService tenantService;
     private String baseUrl;
     
     public DictionaryService getDictionaryService()
@@ -86,16 +83,6 @@ public class SolrIndexerAndSearcherFactory extends AbstractIndexerAndSearcher
         this.queryRegister = queryRegister;
     }
 
-    public TenantService getTenantService()
-    {
-        return tenantService;
-    }
-
-    public void setTenantService(TenantService tenantService)
-    {
-        this.tenantService = tenantService;
-    }
-
     public String getBaseUrl()
     {
         return baseUrl;
@@ -121,15 +108,12 @@ public class SolrIndexerAndSearcherFactory extends AbstractIndexerAndSearcher
     @Override
     public SearchService getSearcher(StoreRef storeRef, boolean searchDelta) throws SearcherException
     {
-        //storeRef = tenantService.getName(storeRef);
-
          SolrSearchService searchService = new SolrSearchService();
          searchService.setDictionaryService(dictionaryService);
          searchService.setNamespacePrefixResolver(namespacePrefixResolver);
          searchService.setNodeService(nodeService);
          searchService.setQueryLanguages(getQueryLanguages());
          searchService.setQueryRegister(queryRegister);
-         searchService.setTenantService(tenantService);
          return searchService;
     }
 
diff --git a/source/java/org/alfresco/repo/search/impl/solr/SolrQueryHTTPClient.java b/source/java/org/alfresco/repo/search/impl/solr/SolrQueryHTTPClient.java
index 326275476a..7a209b736f 100644
--- a/source/java/org/alfresco/repo/search/impl/solr/SolrQueryHTTPClient.java
+++ b/source/java/org/alfresco/repo/search/impl/solr/SolrQueryHTTPClient.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005-2010 Alfresco Software Limited.
+ * Copyright (C) 2005-2011 Alfresco Software Limited.
  *
  * This file is part of Alfresco
  *
@@ -30,15 +30,14 @@ import javax.servlet.http.HttpServletResponse;
 
 import org.alfresco.error.AlfrescoRuntimeException;
 import org.alfresco.httpclient.HttpClientFactory;
-import org.alfresco.model.ContentModel;
 import org.alfresco.repo.domain.node.NodeDAO;
 import org.alfresco.repo.search.impl.lucene.LuceneQueryParserException;
 import org.alfresco.repo.search.impl.lucene.SolrJSONResultSet;
+import org.alfresco.repo.tenant.TenantService;
 import org.alfresco.service.cmr.repository.NodeService;
 import org.alfresco.service.cmr.repository.datatype.DefaultTypeConverter;
 import org.alfresco.service.cmr.search.LimitBy;
 import org.alfresco.service.cmr.search.ResultSet;
-import org.alfresco.service.cmr.search.ResultSetRow;
 import org.alfresco.service.cmr.search.SearchParameters;
 import org.alfresco.service.cmr.search.SearchParameters.FieldFacet;
 import org.alfresco.service.cmr.search.SearchParameters.FieldFacetMethod;
@@ -76,6 +75,8 @@ public class SolrQueryHTTPClient
     private NodeService nodeService;
 
     private PermissionService permissionService;
+    
+    private TenantService tenantService;
 
     private Map<String, String> languageMappings;
 
@@ -121,6 +122,11 @@ public class SolrQueryHTTPClient
     {
         this.permissionService = permissionService;
     }
+    
+    public void setTenantService(TenantService tenantService)
+    {
+        this.tenantService = tenantService;
+    }
 
     public void setLanguageMappings(Map<String, String> languageMappings)
     {
@@ -136,11 +142,6 @@ public class SolrQueryHTTPClient
     {   
         try
         {
-//            Simple demo
-//            FieldFacet ff = new FieldFacet("@"+ContentModel.PROP_NAME);
-//            ff.setLimit(2);
-//            searchParameters.addFieldFacet(ff);
-            
             URLCodec encoder = new URLCodec();
             StringBuilder url = new StringBuilder();
             url.append(baseUrl);
@@ -216,25 +217,9 @@ public class SolrQueryHTTPClient
             }
             url.append(sortBuffer);
 
-            // Authorities go over in body
-
-            StringBuilder authQuery = new StringBuilder();
-            for (String authority : permissionService.getAuthorisations())
-            {
-                if (authQuery.length() > 0)
-                {
-                    authQuery.append(" ");
-                }
-                authQuery.append("|AUTHORITY:\"").append(authority).append("\"");
-            }
-
-            // url.append("&fq=");
-            // encoder = new URLCodec();
-            // url.append(encoder.encode(authQuery.toString(), "UTF-8"));
-
             url.append("&fq=").append(encoder.encode("{!afts}AUTHORITY_FILTER_FROM_JSON", "UTF-8"));
-
-            // facets would go on url?
+            
+            url.append("&fq=").append(encoder.encode("{!afts}TENANT_FILTER_FROM_JSON", "UTF-8"));
 
             if(searchParameters.getFieldFacets().size() > 0)
             {
@@ -275,9 +260,20 @@ public class SolrQueryHTTPClient
             
             JSONObject body = new JSONObject();
             body.put("query", searchParameters.getQuery());
-            // body.put("defaultField", searchParameters.getDefaultFieldName());
 
-            body.put("filter", authQuery);
+            
+            // Authorities go over as is - and tenant mangling and query building takes place on the SOLR side
+
+            JSONArray authorities = new JSONArray();
+            for (String authority : permissionService.getAuthorisations())
+            {
+                authorities.put(authority);
+            }
+            body.put("authorities", authorities);
+            
+            JSONArray tenants = new JSONArray();
+            tenants.put(tenantService.getCurrentUserDomain());
+            body.put("tenants", tenants);
 
             JSONArray locales = new JSONArray();
             for (Locale currentLocale : searchParameters.getLocales())
diff --git a/source/java/org/alfresco/repo/search/impl/solr/SolrSearchService.java b/source/java/org/alfresco/repo/search/impl/solr/SolrSearchService.java
index e33b4a4143..709e3303fb 100644
--- a/source/java/org/alfresco/repo/search/impl/solr/SolrSearchService.java
+++ b/source/java/org/alfresco/repo/search/impl/solr/SolrSearchService.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2005-2010 Alfresco Software Limited.
+ * Copyright (C) 2005-2011 Alfresco Software Limited.
  *
  * This file is part of Alfresco
  *
@@ -34,7 +34,6 @@ import org.alfresco.repo.search.impl.NodeSearcher;
 import org.alfresco.repo.search.impl.lucene.LuceneQueryLanguageSPI;
 import org.alfresco.repo.search.impl.lucene.LuceneQueryParser;
 import org.alfresco.repo.search.impl.lucene.QueryParameterisationException;
-import org.alfresco.repo.tenant.TenantService;
 import org.alfresco.service.cmr.dictionary.DictionaryService;
 import org.alfresco.service.cmr.repository.InvalidNodeRefException;
 import org.alfresco.service.cmr.repository.NodeRef;
@@ -46,8 +45,8 @@ import org.alfresco.service.cmr.search.QueryParameter;
 import org.alfresco.service.cmr.search.QueryParameterDefinition;
 import org.alfresco.service.cmr.search.ResultSet;
 import org.alfresco.service.cmr.search.SearchParameters;
-import org.alfresco.service.cmr.search.SearchService;
 import org.alfresco.service.cmr.search.SearchParameters.Operator;
+import org.alfresco.service.cmr.search.SearchService;
 import org.alfresco.service.namespace.NamespacePrefixResolver;
 import org.alfresco.service.namespace.QName;
 import org.alfresco.util.ISO9075;
@@ -58,11 +57,8 @@ import org.alfresco.util.SearchLanguageConversion;
  */
 public class SolrSearchService implements SearchService
 {
-
     private NodeService nodeService;
     
-    private TenantService tenantService;
-    
     private NamespacePrefixResolver namespacePrefixResolver;
     
     private DictionaryService dictionaryService;
@@ -81,16 +77,6 @@ public class SolrSearchService implements SearchService
         this.nodeService = nodeService;
     }
 
-    public TenantService getTenantService()
-    {
-        return tenantService;
-    }
-
-    public void setTenantService(TenantService tenantService)
-    {
-        this.tenantService = tenantService;
-    }
-
     public NamespacePrefixResolver getNamespacePrefixResolver()
     {
         return namespacePrefixResolver;
@@ -150,8 +136,6 @@ public class SolrSearchService implements SearchService
     @Override
     public ResultSet query(StoreRef store, String language, String query, QueryParameterDefinition[] queryParameterDefinitions)
     {
-        store = tenantService.getName(store);
-
         SearchParameters sp = new SearchParameters();
         sp.addStore(store);
         sp.setLanguage(language);
@@ -164,10 +148,10 @@ public class SolrSearchService implements SearchService
             }
         }
         sp.excludeDataInTheCurrentTransaction(true);
-
+        
         return query(sp);
     }
-
+    
     /*
      * (non-Javadoc)
      * @see org.alfresco.service.cmr.search.SearchService#query(org.alfresco.service.cmr.repository.StoreRef,
@@ -337,10 +321,7 @@ public class SolrSearchService implements SearchService
         {
             throw new IllegalStateException("Only one store can be searched at present");
         }
-
-        ArrayList<StoreRef> stores = searchParameters.getStores();
-        stores.set(0, tenantService.getName(searchParameters.getStores().get(0)));
-
+        
         String parameterisedQueryString;
         if (searchParameters.getQueryParameterDefinitions().size() > 0)
         {
diff --git a/source/java/org/alfresco/repo/solr/AclReaders.java b/source/java/org/alfresco/repo/solr/AclReaders.java
index 41bd96c15f..93cd721040 100644
--- a/source/java/org/alfresco/repo/solr/AclReaders.java
+++ b/source/java/org/alfresco/repo/solr/AclReaders.java
@@ -20,6 +20,8 @@ package org.alfresco.repo.solr;
 
 import java.util.Set;
 
+import org.alfresco.repo.tenant.TenantService;
+
 /**
  * Bean for SOLR ACL readers.
  * 
@@ -31,11 +33,12 @@ public class AclReaders
     private Long aclId;
     private Set<String> readers;
     private long aclChangeSetId;
+    private String tenantDomain = TenantService.DEFAULT_DOMAIN;
     
     @Override
     public String toString()
     {
-        return "AclReaders [aclId=" + aclId + ", readers=" + readers + ", aclChangeSetId=" + aclChangeSetId + "]";
+        return "AclReaders [aclId=" + aclId + ", readers=" + readers + ", aclChangeSetId=" + aclChangeSetId + ", tenantDomain=" + tenantDomain + "]";
     }
     public Long getAclId()
     {
@@ -61,5 +64,12 @@ public class AclReaders
     {
         this.aclChangeSetId = aclChangeSetId;
     }
-    
+    public String getTenantDomain()
+    {
+        return tenantDomain;
+    }
+    public void setTenantDomain(String tenantDomain)
+    {
+        this.tenantDomain = tenantDomain;
+    }
 }
diff --git a/source/java/org/alfresco/repo/solr/NodeMetaData.java b/source/java/org/alfresco/repo/solr/NodeMetaData.java
index c9d61017ae..8cedb17822 100644
--- a/source/java/org/alfresco/repo/solr/NodeMetaData.java
+++ b/source/java/org/alfresco/repo/solr/NodeMetaData.java
@@ -23,7 +23,6 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.zip.CRC32;
 
 import org.alfresco.service.cmr.repository.ChildAssociationRef;
 import org.alfresco.service.cmr.repository.NodeRef;
@@ -50,6 +49,7 @@ public class NodeMetaData
     private Long parentAssocsCrc;
     private List<Long> childIds;
     private Long txnId;
+    private String tenantDomain;
     
     public String getOwner()
     {
@@ -156,6 +156,13 @@ public class NodeMetaData
     public void setTxnId(Long txnId)
     {
         this.txnId = txnId;
-    } 
-    
+    }
+    public String getTenantDomain()
+    {
+        return tenantDomain;
+    }
+    public void setTenantDomain(String tenantDomain)
+    {
+        this.tenantDomain = tenantDomain;
+    }
 }
diff --git a/source/java/org/alfresco/repo/solr/SOLRTrackingComponentImpl.java b/source/java/org/alfresco/repo/solr/SOLRTrackingComponentImpl.java
index 8bc4bd604e..9ff793fcf4 100644
--- a/source/java/org/alfresco/repo/solr/SOLRTrackingComponentImpl.java
+++ b/source/java/org/alfresco/repo/solr/SOLRTrackingComponentImpl.java
@@ -39,6 +39,7 @@ import org.alfresco.repo.domain.node.NodeDAO.ChildAssocRefQueryCallback;
 import org.alfresco.repo.domain.permissions.AclDAO;
 import org.alfresco.repo.domain.qname.QNameDAO;
 import org.alfresco.repo.domain.solr.SOLRDAO;
+import org.alfresco.repo.security.authentication.AuthenticationUtil;
 import org.alfresco.repo.tenant.TenantService;
 import org.alfresco.service.cmr.dictionary.AspectDefinition;
 import org.alfresco.service.cmr.dictionary.DataTypeDefinition;
@@ -185,6 +186,8 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
              * This is an N+1 query that should, in theory, make use of cached ACL readers data.
              */
 
+            Map<Long, String> aclChangeSetTenant = new HashMap<Long, String>(aclIds.size());
+            
             List<AclReaders> aclsReaders = new ArrayList<AclReaders>(aclIds.size() * 10);
             for (Long aclId : aclIds)
             {
@@ -192,10 +195,30 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
                 AclReaders readers = new AclReaders();
                 readers.setAclId(aclId);
                 readers.setReaders(readersSet);
-                readers.setAclChangeSetId(aclDAO.getAccessControlList(aclId).getProperties().getAclChangeSetId());
+                
+                Long aclChangeSetId = aclDAO.getAccessControlList(aclId).getProperties().getAclChangeSetId();
+                readers.setAclChangeSetId(aclChangeSetId);
+                
+                if (AuthenticationUtil.isMtEnabled())
+                {
+                	// MT - for now, derive the tenant for acl (via acl change set)
+                    String tenantDomain = aclChangeSetTenant.get(aclChangeSetId);
+                    if (tenantDomain == null)
+                    {
+                        tenantDomain = getTenant(aclId, aclChangeSetId);
+                        if (tenantDomain == null)
+                        {
+                            // skip this acl !
+                            continue;
+                        }
+                        aclChangeSetTenant.put(aclChangeSetId, tenantDomain);
+                    }
+                    readers.setTenantDomain(tenantDomain);
+                }
+                
                 aclsReaders.add(readers);
             }
-
+            
             return aclsReaders;
         }
         else
@@ -203,7 +226,51 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
             return Collections.<AclReaders>emptyList();
         }
     }
-
+    
+    private String getTenant(long aclId, long aclChangeSetId)
+    {
+        String tenantDomain = getAclTenant(aclId);
+        if (tenantDomain == null)
+        {
+            List<Long> aclChangeSetIds = new ArrayList<Long>(1);
+            aclChangeSetIds.add(aclChangeSetId);
+            
+            List<Acl> acls = solrDAO.getAcls(aclChangeSetIds, null, 1024);
+            for (Acl acl : acls)
+            {
+                tenantDomain = getAclTenant(acl.getId());
+                if (tenantDomain != null)
+                {
+                    break;
+                }
+            }
+            
+            if (tenantDomain == null)
+            {
+                // tenant not found - log warning ?
+                tenantDomain = null; // temp - for debug breakpoint only
+            }
+        }
+        return tenantDomain;
+    }
+    
+    private String getAclTenant(long aclId)
+    {
+        List<Long> nodeIds = aclDAO.getADMNodesByAcl(aclId, 1);
+        if (nodeIds.size() == 0)
+        {
+            return null;
+        }
+        
+        Pair<Long, NodeRef> nodePair = nodeDAO.getNodePair(nodeIds.get(0));
+        if (nodePair == null)
+        {
+            return null;
+        }
+        
+        return tenantService.getDomain(nodePair.getSecond().getStoreRef().getIdentifier());
+    }
+    
     @Override
     public List<Transaction> getTransactions(Long minTxnId, Long fromCommitTime, int maxResults)
     {
@@ -519,12 +586,16 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
 
                 nodeMetaData.setPaths(paths);
             }
-
+            
+            NodeRef nodeRef = pair.getSecond();
+            
             if(includeNodeRef)
             {
-                nodeMetaData.setNodeRef(pair.getSecond());
+                nodeMetaData.setNodeRef(tenantService.getBaseName(nodeRef, true));
             }
-        
+            
+            nodeMetaData.setTenantDomain(tenantService.getDomain(nodeRef.getStoreRef().getIdentifier()));
+            
             if(includeChildAssociations)
             {
                 final List<ChildAssociationRef> childAssocs = new ArrayList<ChildAssociationRef>(100);
@@ -546,7 +617,7 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
                     public boolean handle(Pair<Long, ChildAssociationRef> childAssocPair, Pair<Long, NodeRef> parentNodePair,
                             Pair<Long, NodeRef> childNodePair)
                     {
-                        childAssocs.add(childAssocPair.getSecond());
+                        childAssocs.add(tenantService.getBaseName(childAssocPair.getSecond(), true));
                         return true;
                     }
                     
@@ -612,7 +683,7 @@ public class SOLRTrackingComponentImpl implements SOLRTrackingComponent
                     public boolean handle(Pair<Long, ChildAssociationRef> childAssocPair,
                             Pair<Long, NodeRef> parentNodePair, Pair<Long, NodeRef> childNodePair)
                     {
-                        parentAssocs.add(childAssocPair.getSecond());
+                        parentAssocs.add(tenantService.getBaseName(childAssocPair.getSecond(), true));
                         return true;
                     }
 
diff --git a/source/java/org/alfresco/repo/tenant/MultiTServiceImpl.java b/source/java/org/alfresco/repo/tenant/MultiTServiceImpl.java
index fe3bf5b3e5..5a3e039476 100644
--- a/source/java/org/alfresco/repo/tenant/MultiTServiceImpl.java
+++ b/source/java/org/alfresco/repo/tenant/MultiTServiceImpl.java
@@ -277,10 +277,17 @@ public class MultiTServiceImpl implements TenantService
      * @see org.alfresco.repo.tenant.TenantService#getBaseName(org.alfresco.service.cmr.repository.NodeRef)
      */
     public NodeRef getBaseName(NodeRef nodeRef)
-    { 
+    {
+        return getBaseName(nodeRef, false);
+    }
+    
+    /* (non-Javadoc)
+     * @see org.alfresco.repo.tenant.TenantService#getBaseName(org.alfresco.service.cmr.repository.NodeRef, boolean)
+     */
+    public NodeRef getBaseName(NodeRef nodeRef, boolean forceForNonTenant)
+    {
         if (nodeRef == null) { return null; }
-
-        return new NodeRef(nodeRef.getStoreRef().getProtocol(), getBaseName(nodeRef.getStoreRef().getIdentifier()), nodeRef.getId());
+        return new NodeRef(nodeRef.getStoreRef().getProtocol(), getBaseName(nodeRef.getStoreRef().getIdentifier(), forceForNonTenant), nodeRef.getId());
     }
     
     /* (non-Javadoc)
@@ -298,13 +305,21 @@ public class MultiTServiceImpl implements TenantService
      */
     public ChildAssociationRef getBaseName(ChildAssociationRef childAssocRef)
     {
+        return getBaseName(childAssocRef, false);
+    }
+    
+    /* (non-Javadoc)
+     * @see org.alfresco.repo.tenant.TenantService#getBaseName(org.alfresco.service.cmr.repository.ChildAssociationRef, boolean)
+     */
+    public ChildAssociationRef getBaseName(ChildAssociationRef childAssocRef, boolean forceForNonTenant)
+    {
         if (childAssocRef == null) { return null; }
         
         return new ChildAssociationRef(
                 childAssocRef.getTypeQName(),
-                getBaseName(childAssocRef.getParentRef()),
+                getBaseName(childAssocRef.getParentRef(), forceForNonTenant),
                 childAssocRef.getQName(),
-                getBaseName(childAssocRef.getChildRef()),
+                getBaseName(childAssocRef.getChildRef(), forceForNonTenant),
                 childAssocRef.isPrimary(), 
                 childAssocRef.getNthSibling());
     }