Thanks Caroline,

I decided to use variables in a case statements:

LOCAL lcwhere1, lcwhere2, lcwhere3
SET EXCLUSIVE OFF
SET DELETED ON

lcwhere1="modacad.key3=thisform.combo1.displayvalue"
lcwhere2="modacad.key3==thisform.combo1.displayvalue"
lcwhere3="modacad.key3$thisform.combo1.displayvalue"

DO CASE 
	CASE 1
		IF thisform.combo1.displayvalue='='
			SELECT * ;
			FROM ("U:\Data\modacad.dbf") ;
			WHERE lcwhere1 ;
			order BY mainkey ;
			INTO CURSOR crssearch
		ENDIF
	CASE 2
		IF thisform.combo1.displayvalue='=='
			SELECT * ;
			FROM ("U:\Data\modacad.dbf") ;
			WHERE lcwhere2 ;
			order BY mainkey ;
			INTO CURSOR crssearch
		ENDIF
	CASE 3
		IF thisform.combo1.displayvalue='$'
			SELECT * ;
			FROM ("U:\Data\modacad.dbf") ;
			WHERE lcwhere3 ;
			order BY mainkey ;
			INTO CURSOR crssearch
		ENDIF

ENDCASE

I get a syntax error. Do you have any ideas as to why this doesn't work?

Thanks Caroline