This chapter examines the effect of commercialisation of microfinance on the performance measurement practices of MFIs and the implications these measurement practices have on the achievement of the mission objectives of MFIs using as a case, the microfinance industry in Ghana. Mainly qualitative research techniques were employed in the study, relying on the views and perspectives of MFIs, clients, practitioners, and experts. The study results indicate that MFIs have not appropriately met this dual expectation of pursuing both financial and social objectives and cannot therefore possibly improve their understanding of the mission drift phenomenon with their existing measurement practices. The authors therefore propose a conceptual framework, as well as core social and economic performance, and impact indicators for measuring the attainment of the double bottom line or convergence.