diff --git a/include/yazproxy/proxy.h b/include/yazproxy/proxy.h
index c2d295c..5a7eafe 100644
--- a/include/yazproxy/proxy.h
+++ b/include/yazproxy/proxy.h
@@ -131,6 +131,7 @@ class YAZ_EXPORT Yaz_Proxy : public yazpp_1::Z_Assoc {
     Z_APDU *handle_target_charset_conversion(Z_APDU *apdu);
 
     Z_APDU *handle_syntax_validation(Z_APDU *apdu);
+    Z_APDU *handle_database_validation(Z_APDU *apdu);
 
     void handle_charset_lang_negotiation(Z_APDU *apdu);
 
diff --git a/src/proxyp.h b/src/proxyp.h
index f791372..101f796 100644
--- a/src/proxyp.h
+++ b/src/proxyp.h
@@ -148,6 +148,7 @@ class Yaz_ProxyConfig {
     char *get_explain_doc(ODR odr, const char *name, const char *db,
                           int *len, int *http_status);
     const char *get_explain_name(const char *db, const char **backend_db);
+    int check_is_defined_database(const char *name, const char *db);
  private:
     void operator=(const Yaz_ProxyConfig &conf);
     class Yaz_ProxyConfigP *m_cp;
diff --git a/src/yaz-proxy-config.cpp b/src/yaz-proxy-config.cpp
index ae235d5..6720fa1 100644
--- a/src/yaz-proxy-config.cpp
+++ b/src/yaz-proxy-config.cpp
@@ -484,6 +484,30 @@ int Yaz_ProxyConfigP::check_type_1(ODR odr, xmlNodePtr ptr, Z_RPNQuery *query,
 }
 #endif
 
+int Yaz_ProxyConfig::check_is_defined_database(const char *name, const char *db) {
+#if YAZ_HAVE_XSLT
+    xmlNodePtr ptr;
+    struct _xmlAttr *attr;
+    
+    ptr = m_cp->find_target_node(name);
+        
+    if (ptr)
+    {    
+        for (attr = ptr->properties; attr; attr = attr->next)
+        {
+            if (attr->children && attr->children->type == XML_TEXT_NODE) {
+                if (!strcmp((const char *)attr->name, "database")
+                    && !strcmp((const char *)attr->children->content, db))
+                {
+                    return 1;
+                }
+            }                        
+        }
+    }
+#endif
+    return 0;
+}
+
 int Yaz_ProxyConfig::check_query(ODR odr, const char *name, Z_Query *query,
                                  char **addinfo)
 {
diff --git a/src/yaz-proxy.cpp b/src/yaz-proxy.cpp
index 351725b..21dee1b 100644
--- a/src/yaz-proxy.cpp
+++ b/src/yaz-proxy.cpp
@@ -2695,6 +2695,34 @@ int Yaz_Proxy::handle_global_authentication(Z_APDU *apdu)
     return ret;
 }
 
+Z_APDU *Yaz_Proxy::handle_database_validation(Z_APDU *apdu)
+{
+    Yaz_ProxyConfig *cfg = check_reconfigure();
+
+    if (cfg && apdu->which == Z_APDU_searchRequest)
+    {        
+        Z_SearchRequest *sr = apdu->u.searchRequest;
+
+        for (int i = 0; i < sr->num_databaseNames; i++) {
+            // This works only with the default target
+            if (!cfg->check_is_defined_database(m_default_target, (const char *)sr->databaseNames[i])) {
+                Z_APDU *new_apdu = create_Z_PDU(Z_APDU_searchResponse);
+
+                new_apdu->u.searchResponse->referenceId = sr->referenceId;
+                new_apdu->u.searchResponse->records =
+                    create_nonSurrogateDiagnostics(odr_encode(), YAZ_BIB1_ACCESS_TO_SPECIFIED_DATABASE_DENIED, NULL);
+                *new_apdu->u.searchResponse->searchStatus = 0;
+
+                send_to_client(new_apdu);
+
+                return 0;
+            }
+        }            
+    }
+
+    return apdu;
+}
+
 Z_APDU *Yaz_Proxy::handle_syntax_validation(Z_APDU *apdu)
 {
     m_marcxml_mode = none;
@@ -3647,6 +3675,9 @@ void Yaz_Proxy::handle_incoming_Z_PDU_2(Z_APDU *apdu)
 {
     handle_max_record_retrieve(apdu);
 
+    if (apdu)
+        apdu = handle_database_validation(apdu);
+
     if (apdu)
         apdu = handle_syntax_validation(apdu);