diff --git a/doc/sql.extensions/README.ddl.txt b/doc/sql.extensions/README.ddl.txt
index 48ded29b41..fe716ad891 100644
--- a/doc/sql.extensions/README.ddl.txt
+++ b/doc/sql.extensions/README.ddl.txt
@@ -158,6 +158,7 @@ basic_type:
 - PACKAGE
 - USER (ability to store comment depends upon user management plugin)
 - SECURITY CLASS (not implemented because Borland hid them).
+- [GLOBAL] MAPPING
 
 
 5) Allow setting and dropping default values from table fields.
diff --git a/src/dsql/DdlNodes.epp b/src/dsql/DdlNodes.epp
index 6cb8316c99..05893c7686 100644
--- a/src/dsql/DdlNodes.epp
+++ b/src/dsql/DdlNodes.epp
@@ -10500,6 +10500,7 @@ string MappingNode::internalPrint(NodePrinter& printer) const
 	NODE_PRINT(printer, fromType);
 	NODE_PRINT(printer, from);
 	NODE_PRINT(printer, to);
+	NODE_PRINT(printer, comment);
 	NODE_PRINT(printer, op);
 	NODE_PRINT(printer, mode);
 	NODE_PRINT(printer, global);
@@ -10558,10 +10559,22 @@ void MappingNode::runInSecurityDb(SecDbContext* secDbContext)
 	case MAP_RPL:
 		ddl = "CREATE OR ALTER MAPPING ";
 		break;
+	case MAP_COMMENT:
+		ddl = "COMMENT ON MAPPING ";
+		break;
+	}
+	addItem(ddl, name.c_str());
+
+	if (op == MAP_COMMENT)
+	{
+		ddl += " IS ";
+		if (comment)
+			addItem(ddl, comment->c_str(), '\'');
+		else
+			ddl += "NULL";
 	}
 
-	addItem(ddl, name.c_str());
-	if (op != MAP_DROP)
+	else if (op != MAP_DROP)
 	{
 		ddl += " USING ";
 		switch (mode)
@@ -10654,6 +10667,7 @@ void MappingNode::runInSecurityDb(SecDbContext* secDbContext)
 					(Arg::Gds(isc_map_already_exists) << name).raise();
 				break;
 
+			case MAP_COMMENT:
 			case MAP_MOD:
 			case MAP_DROP:
 				if (!hasLine)
@@ -10676,6 +10690,10 @@ void MappingNode::runInSecurityDb(SecDbContext* secDbContext)
 			Field<Varying> f2(full, 255);
 			Field<Varying> nm2(full, MAX_SQL_IDENTIFIER_LEN);
 
+			Message cmnt;
+			Field<Varying> c3(cmnt, MAX_VARY_COLUMN_SIZE);
+			Field<Varying> nm3(cmnt, MAX_SQL_IDENTIFIER_LEN);
+
 			toType = role ? 1 : 0;
 			if (to)
 				t = to->c_str();
@@ -10688,7 +10706,9 @@ void MappingNode::runInSecurityDb(SecDbContext* secDbContext)
 				type2 = fromType->c_str();
 			if (from)
 				f2 = fromUtf8.c_str();
-			nm2 = name.c_str();
+			if (comment)
+				c3 = comment->c_str();
+			nm3 = nm2 = name.c_str();
 
 			Message* msg = NULL;
 			const char* sql = NULL;
@@ -10707,6 +10727,11 @@ void MappingNode::runInSecurityDb(SecDbContext* secDbContext)
 					"where RDB$MAP_NAME = ?";
 				msg = &full;
 				break;
+			case MAP_COMMENT:
+				sql = "update RDB$AUTH_MAPPING set RDB$DESCRIPTION = ? "
+					"where RDB$MAP_NAME = ?";
+				msg = &cmnt;
+				break;
 			case MAP_DROP:
 				sql = "delete from RDBAUTH_MAPPING where RDB$MAP_NAME = ?";
 				msg = &msgCheck;
@@ -10751,7 +10776,7 @@ void MappingNode::execute(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch, jrd
 	// run all statements under savepoint control
 	AutoSavePoint savePoint(tdbb, transaction);
 
-	fb_assert(op == MAP_DROP || fromType);
+	fb_assert(op == MAP_DROP || op == MAP_COMMENT || fromType);
 
 	short plugNull = plugin ? FALSE  : TRUE;
 	short dbNull = db ? FALSE : TRUE;
@@ -10807,6 +10832,17 @@ void MappingNode::execute(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch, jrd
 			END_MODIFY
 			break;
 
+		case MAP_COMMENT:
+			MODIFY M
+				M.RDB$DESCRIPTION.NULL = !(comment && comment->hasData());
+				if (!M.RDB$DESCRIPTION.NULL)
+				{
+					AutoBlb b(tdbb, blb::create(tdbb, transaction, &M.RDB$DESCRIPTION));
+					b->BLB_put_data(tdbb, (const UCHAR*)(comment->c_str()), comment->length());
+				}
+			END_MODIFY
+			break;
+
 		case MAP_DROP:
 			ddlTriggerAction = DDL_TRIGGER_DROP_MAPPING;
 			executeDdlTrigger(tdbb, dsqlScratch, transaction, DTW_BEFORE, ddlTriggerAction,
@@ -10870,16 +10906,18 @@ void MappingNode::execute(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch, jrd
 
 	case MAP_MOD:
 	case MAP_DROP:
+	case MAP_COMMENT:
 		if (!found)
 			(Arg::Gds(isc_map_not_exists) << name).raise();
 		break;
 	}
 
-	fb_assert(ddlTriggerAction > 0);
+	fb_assert(ddlTriggerAction > 0 || op == MAP_COMMENT);
 	if (ddlTriggerAction > 0)
 		executeDdlTrigger(tdbb, dsqlScratch, transaction, DTW_AFTER, ddlTriggerAction, name, NULL);
 
-	DFW_post_work(transaction, dfw_clear_cache, NULL, Mapping::MAPPING_CACHE);
+	if (op != MAP_COMMENT)
+		DFW_post_work(transaction, dfw_clear_cache, NULL, Mapping::MAPPING_CACHE);
 	savePoint.release();	// everything is ok
 }
 
diff --git a/src/dsql/DdlNodes.h b/src/dsql/DdlNodes.h
index 4686f94eab..a6752333f2 100644
--- a/src/dsql/DdlNodes.h
+++ b/src/dsql/DdlNodes.h
@@ -2066,7 +2066,7 @@ private:
 class MappingNode : public DdlNode, private ExecInSecurityDb
 {
 public:
-	enum OP {MAP_ADD, MAP_MOD, MAP_RPL, MAP_DROP};
+	enum OP {MAP_ADD, MAP_MOD, MAP_RPL, MAP_DROP, MAP_COMMENT};
 
 	MappingNode(MemoryPool& p, OP o, const MetaName& nm)
 		: DdlNode(p),
@@ -2077,6 +2077,7 @@ public:
 		  fromType(NULL),
 		  from(NULL),
 		  to(NULL),
+		  comment(NULL),
 		  op(o),
 		  mode('#'),
 		  global(false),
@@ -2096,7 +2097,8 @@ protected:
 	{
 		statusVector << Firebird::Arg::Gds(isc_dsql_mapping_failed) << name <<
 			(op == MAP_ADD ? "CREATE" : op == MAP_MOD ?
-			 "ALTER" : op == MAP_RPL ? "CREATE OR ALTER" : "DROP");
+			 "ALTER" : op == MAP_RPL ? "CREATE OR ALTER" : op == MAP_DROP ?
+			 "DROP" : "COMMENT ON");
 	}
 	void runInSecurityDb(SecDbContext* secDbContext);
 
@@ -2111,6 +2113,7 @@ public:
 	MetaName* fromType;
 	IntlString* from;
 	MetaName* to;
+	Firebird::string* comment;
 	OP op;
 	char mode;	// * - any source, P - plugin, M - mapping, S - any serverwide plugin
 	bool global;
diff --git a/src/dsql/parse.y b/src/dsql/parse.y
index 7059de994a..e2e04f8295 100644
--- a/src/dsql/parse.y
+++ b/src/dsql/parse.y
@@ -5651,6 +5651,8 @@ comment
 		{ $$ = newNode<CommentOnNode>($3, *$4, "", *$6); }
 	| comment_on_user
 		{ $$ = $1; }
+	| comment_on_mapping
+		{ $$ = $1; }
 	;
 
 %type <createAlterUserNode> comment_on_user
@@ -7307,6 +7309,28 @@ drop_map_clause($global)
 		}
 	;
 
+%type <mappingNode> comment_on_mapping
+comment_on_mapping
+	: COMMENT ON MAPPING map_comment(false)
+		{
+			$$ = $4;
+		}
+	| COMMENT ON GLOBAL MAPPING map_comment(true)
+		{
+			$$ = $5;
+		}
+	;
+
+%type <mappingNode> map_comment(<boolVal>)
+map_comment($global)
+	: map_name IS ddl_desc
+		{
+ 			$$ = newNode<MappingNode>(MappingNode::MAP_COMMENT, *$1);
+			$$->global = $global;
+			$$->comment = $3;
+		}
+	;
+
 %type <mappingNode> map_clause(<mappingOp>)
 map_clause($op)
 	: map_name
diff --git a/src/jrd/Mapping.cpp b/src/jrd/Mapping.cpp
index 003f18c476..19bf57a8ae 100644
--- a/src/jrd/Mapping.cpp
+++ b/src/jrd/Mapping.cpp
@@ -1725,10 +1725,11 @@ RecordBuffer* MappingList::getList(thread_db* tdbb, jrd_rel* relation)
 		Field<Varying> from(mMap, 255);
 		Field<SSHORT> role(mMap);
 		Field<Varying> to(mMap, MAX_SQL_IDENTIFIER_SIZE);
+		Field<ISC_QUAD> desc(mMap);
 
 		curs = att->openCursor(&st, tra, 0,
 			"SELECT RDB$MAP_NAME, RDB$MAP_USING, RDB$MAP_PLUGIN, RDB$MAP_DB, "
-			"	RDB$MAP_FROM_TYPE, RDB$MAP_FROM, RDB$MAP_TO_TYPE, RDB$MAP_TO "
+			"	RDB$MAP_FROM_TYPE, RDB$MAP_FROM, RDB$MAP_TO_TYPE, RDB$MAP_TO, RDB$DESCRIPTION "
 			"FROM RDB$AUTH_MAPPING",
 			3, nullptr, nullptr, mMap.getMetadata(), nullptr, 0);
 		if (st->getState() & IStatus::STATE_ERRORS)
@@ -1798,6 +1799,20 @@ RecordBuffer* MappingList::getList(thread_db* tdbb, jrd_rel* relation)
 						 DumpField(f_sec_map_to, VALUE_STRING, to->len, to->data));
 			}
 
+			if (!desc.null)
+			{
+				RefPtr<IBlob> blb(REF_NO_INCR, att->openBlob(&st, tra, &desc, 0, nullptr));
+				check("IAttachment::openBlob", &st);
+				string buf;
+				const FB_SIZE_T FLD_LIMIT = MAX_COLUMN_SIZE;
+				unsigned length = 0;
+				blb->getSegment(&st, FLD_LIMIT, buf.getBuffer(FLD_LIMIT), &length);
+				check("IBlob::getSegment", &st);
+
+				putField(tdbb, record,
+					DumpField(f_sec_map_comment, VALUE_STRING, length, buf.c_str()));
+			}
+
 			buffer->store(record);
 		}
 		check("IResultSet::fetchNext", &st);
diff --git a/src/jrd/relations.h b/src/jrd/relations.h
index 1016ad7c8e..d9e1b03110 100644
--- a/src/jrd/relations.h
+++ b/src/jrd/relations.h
@@ -685,6 +685,7 @@ RELATION(nam_sec_global_auth_mapping, rel_global_auth_mapping, ODS_12_0, rel_vir
 	FIELD(f_sec_map_from, nam_sec_map_from, fld_map_from, 0, ODS_12_0)
 	FIELD(f_sec_map_to_type, nam_sec_map_to_type, fld_obj_type, 0, ODS_12_0)
 	FIELD(f_sec_map_to, nam_sec_map_to, fld_map_to, 0, ODS_12_0)
+	FIELD(f_sec_map_comment, nam_sec_description, fld_description, 0, ODS_13_1)
 END_RELATION
 
 // Relation 47 (RDB$DB_CREATORS)