diff --git a/lib/src/clixon_yang_parse.l b/lib/src/clixon_yang_parse.l
index f032c814..f0a769fe 100644
--- a/lib/src/clixon_yang_parse.l
+++ b/lib/src/clixon_yang_parse.l
@@ -93,6 +93,7 @@ identifier      [A-Za-z_][A-Za-z0-9_\-\.]*
 
 %x KEYWORD
 %x DEVIATE
+%x DEVIATESTR
 %s BOOLEAN
 %s INTEGER
 %s STRARG
@@ -107,12 +108,12 @@ identifier      [A-Za-z_][A-Za-z0-9_\-\.]*
 
 %%
  /* Common tokens */
-<KEYWORD,DEVIATE,BOOLEAN,INTEGER,STRARG,STRING>[ \t]            
-<KEYWORD,DEVIATE,STRING,UNKNOWN,UNKNOWN2,COMMENT2><<EOF>> { return MY_EOF; }
-<KEYWORD,DEVIATE,BOOLEAN,INTEGER,STRARG,STRING,COMMENT1,UNKNOWN,UNKNOWN2>\n   { _YY->yy_linenum++; }
-<KEYWORD,DEVIATE,BOOLEAN,INTEGER,STRARG,STRING,COMMENT1,UNKNOWN,UNKNOWN2>\r   
-<KEYWORD,DEVIATE,STRING,UNKNOWN,UNKNOWN2>"/*"    { _YY->yy_lex_state = YYSTATE; BEGIN(COMMENT1); }
-<KEYWORD,DEVIATE,STRING,UNKNOWN,UNKNOWN2>"//"    { _YY->yy_lex_state = YYSTATE; BEGIN(COMMENT2); }
+<KEYWORD,DEVIATE,DEVIATESTR,BOOLEAN,INTEGER,STRARG,STRING>[ \t]            
+<KEYWORD,DEVIATE,DEVIATESTR,STRING,UNKNOWN,UNKNOWN2,COMMENT2><<EOF>> { return MY_EOF; }
+<KEYWORD,DEVIATE,DEVIATESTR,BOOLEAN,INTEGER,STRARG,STRING,COMMENT1,UNKNOWN,UNKNOWN2>\n   { _YY->yy_linenum++; }
+<KEYWORD,DEVIATE,DEVIATESTR,BOOLEAN,INTEGER,STRARG,STRING,COMMENT1,UNKNOWN,UNKNOWN2>\r   
+<KEYWORD,DEVIATE,DEVIATESTR,STRING,UNKNOWN,UNKNOWN2>"/*"    { _YY->yy_lex_state = YYSTATE; BEGIN(COMMENT1); }
+<KEYWORD,DEVIATE,DEVIATESTR,STRING,UNKNOWN,UNKNOWN2>"//"    { _YY->yy_lex_state = YYSTATE; BEGIN(COMMENT2); }
 
 
 <KEYWORD>input            { return K_INPUT; } /* No argument */
@@ -202,7 +203,14 @@ identifier      [A-Za-z_][A-Za-z0-9_\-\.]*
 <DEVIATE>add              { BEGIN(KEYWORD); return D_ADD; }
 <DEVIATE>delete           { BEGIN(KEYWORD); return D_DELETE; }
 <DEVIATE>replace          { BEGIN(KEYWORD); return D_REPLACE; }
+<DEVIATE>\"               { BEGIN(DEVIATESTR); return *yytext; }
+<DEVIATE>\'               { BEGIN(DEVIATESTR); return *yytext; }
 <DEVIATE>.                { BEGIN(KEYWORD); return *yytext; }
+<DEVIATESTR>not-supported { return D_NOT_SUPPORTED; }
+<DEVIATESTR>add           { return D_ADD; }
+<DEVIATESTR>delete        { return D_DELETE; }
+<DEVIATESTR>replace       { return D_REPLACE; }
+<DEVIATESTR>.             { BEGIN(KEYWORD); return *yytext; }
 <UNKNOWN>:                { return *yytext; }
 <UNKNOWN>;                { BEGIN(KEYWORD); return *yytext; }
 <UNKNOWN>\{               { BEGIN(KEYWORD); return *yytext; }
diff --git a/lib/src/clixon_yang_parse.y b/lib/src/clixon_yang_parse.y
index fd939aa0..6c44b2b9 100644
--- a/lib/src/clixon_yang_parse.y
+++ b/lib/src/clixon_yang_parse.y
@@ -1529,16 +1529,26 @@ deviation_substmt : description_stmt  { _PARSE_DEBUG("deviation-substmt -> descr
                   | deviate_replace_stmt { _PARSE_DEBUG("deviation-stmt -> deviate-replace-stmt");}
 		  ;
 
+not_supported_keyword_str : D_NOT_SUPPORTED
+                          | '"' D_NOT_SUPPORTED '"'
+                          | SQ D_NOT_SUPPORTED SQ
+                          ;
+
 deviate_not_supported_stmt
-                  : K_DEVIATE D_NOT_SUPPORTED ';'
-		  { if (ysp_add(_yy, Y_DEVIATE, strdup("not-supported") /* D_NOT_SUPPORTED*/, NULL) == NULL) _YYERROR("notification_stmt");
+                  : K_DEVIATE not_supported_keyword_str ';'
+		  { if (ysp_add(_yy, Y_DEVIATE, strdup("not-supported"), NULL) == NULL) _YYERROR("notification_stmt");
     			   _PARSE_DEBUG("deviate-not-supported-stmt -> DEVIATE not-supported ;"); }
                   ;
 
-deviate_add_stmt   : K_DEVIATE D_ADD ';'
-                  { if (ysp_add(_yy, Y_DEVIATE, strdup("add") /* D_NOT_SUPPORTED*/, NULL) == NULL) _YYERROR("notification_stmt");
+add_keyword_str    : D_ADD 
+                   | '"' D_ADD '"'
+                   | SQ D_ADD SQ
+                   ;
+
+deviate_add_stmt   : K_DEVIATE add_keyword_str ';'
+                  { if (ysp_add(_yy, Y_DEVIATE, strdup("add"), NULL) == NULL) _YYERROR("notification_stmt");
     			   _PARSE_DEBUG("deviate-add-stmt -> DEVIATE add ;"); }
-                  | K_DEVIATE D_ADD
+                  | K_DEVIATE add_keyword_str
 		  { if (ysp_add_push(_yy, Y_DEVIATE, strdup("add"), NULL) == NULL) _YYERROR("deviate_stmt"); }
 	            '{' deviate_add_substmts '}' 
                         { if (ystack_pop(_yy) < 0) _YYERROR("deviate_stmt");
@@ -1562,10 +1572,15 @@ deviate_add_substmt : units_stmt    { _PARSE_DEBUG("deviate-add-substmt -> units
                 ;
 
 
-deviate_delete_stmt   : K_DEVIATE D_DELETE ';'
+delete_keyword_str : D_DELETE 
+                   | '"' D_DELETE '"'
+                   | SQ D_DELETE SQ
+                   ;
+
+deviate_delete_stmt   : K_DEVIATE delete_keyword_str ';'
                   { if (ysp_add(_yy, Y_DEVIATE, strdup("delete"), NULL) == NULL) _YYERROR("notification_stmt");
     			   _PARSE_DEBUG("deviate-delete-stmt -> DEVIATE delete ;"); }
-                  | K_DEVIATE D_DELETE
+                  | K_DEVIATE delete_keyword_str
 		  { if (ysp_add_push(_yy, Y_DEVIATE, strdup("delete"), NULL) == NULL) _YYERROR("deviate_stmt"); }
 	            '{' deviate_delete_substmts '}' 
                         { if (ystack_pop(_yy) < 0) _YYERROR("deviate_stmt");
@@ -1584,10 +1599,15 @@ deviate_delete_substmt : units_stmt { _PARSE_DEBUG("deviate-delete-substmt -> un
                 |                   { _PARSE_DEBUG("deviate-delete-substmt -> "); }
                 ;
 
-deviate_replace_stmt   : K_DEVIATE D_REPLACE ';'
+replace_keyword_str : D_REPLACE 
+                   | '"' D_REPLACE '"'
+                   | SQ D_REPLACE SQ
+                   ;
+
+deviate_replace_stmt   : K_DEVIATE replace_keyword_str ';'
                   { if (ysp_add(_yy, Y_DEVIATE, strdup("replace"), NULL) == NULL) _YYERROR("notification_stmt");
     			   _PARSE_DEBUG("deviate-replace-stmt -> DEVIATE replace ;"); }
-                  | K_DEVIATE D_REPLACE
+                  | K_DEVIATE replace_keyword_str
 		  { if (ysp_add_push(_yy, Y_DEVIATE, strdup("replace"), NULL) == NULL) _YYERROR("deviate_stmt"); }
 	            '{' deviate_replace_substmts '}' 
                         { if (ystack_pop(_yy) < 0) _YYERROR("deviate_stmt");
diff --git a/test/test_yang_deviation.sh b/test/test_yang_deviation.sh
index 654a6385..8d4e6170 100755
--- a/test/test_yang_deviation.sh
+++ b/test/test_yang_deviation.sh
@@ -175,7 +175,7 @@ module example-deviations{
          prefix base;
    }
    deviation /base:system/base:daytime {
-      deviate not-supported;
+      deviate "not-supported"; // Note a string
    }
 }
 EOF