hi ... use Linlin's data and Tom's data step, insert PROC SQL in between to find the maximum length of the combined data across the IDs data have; input id line $50.; cards; 100 abcdefghijkollldsdksjd 100 djsjdklsjdksdlsldklskdsld 100 djskdjsldjlsdjlsdjlsdljskdjskdjskdioeioeoeoe 100 jksldksldklsldklsdksldksldklskdls 100 djsldksldksldklsdkdadskldkasldklsdksdklskdsk 200 djksldklskdlskdls 200 uuuuuuuuuuuuuuuuuu ; proc sql noprint; select max(lng) into :maxlng separated by ' ' from (select sum(length(line)) as lng from have group by id) ; quit; data want ;   length newvar $&maxlng;   do until (last.id);     set have;     by id;     newvar=cats(newvar,line);   end;   drop line; run; ps the "separated by" removes any blanks from around the value of the  macro variable ... http://www.sascommunity.org/wiki/Tips:Strip_Blanks_from_PROC_SQL-Created_Macro_Variable_Values ... View more