Hi, say: >>> import re >>>> m="oooocccvlvlvlvnnnflfllffccclfnnnooo" >>> re.compile(r'ccc.*nnn') >>> rtt=pppp.sub("||",m) >>> rtt 'oooo||ooo' The regex is eating up too much. What I want is every non-overlapping occurrence I think. so rtt would be: 'oooo||flfllff||ooo' just like findall acts but in this case I want sub to act like that. Thanks