All, Say I have a string "l" ... l = 'PBUSH 201005 K 1. 1. 1. 1. 1. 1.' And I want to replace the first " 1." with a "500.2" and the second " 1." with " 5.2" ... What pythonic means would you all recommend? Note the whitespace is equal between the existing substring and the replacement string. Many thanks, Ben Racine i3enhamin at gmail.com