Public sector reforms are commonplace in developing countries. Much of the literature about these reforms reflects on their failures. This paper asks about the successes and investigates which of two competing theories best explain why some reforms exhibit such positive deviance. These theories are called 'solution and leader driven change' (SLDC) and 'problem driven iterative adaptation' (PDIA). They are used to analyze data emerging from a case survey involving thirty cases from Princeton University's Innovations for Successful Society (ISS) program. The bulk of evidence from this study supports a PDIA explanation, but there is reason to believe that SLDC hypotheses also have value. It seems that PDIA and SLDC are two viable paths through which positive deviance can emerge; although PDIA seems to provide the wider path for more positive deviance.