Over the last 10 to 15 years, an increasing number of countries have been reforming their microfinance regulatory frameworks. Despite substantial practical experience in many countries with the preferred approach of regulating microfinance under specialised laws, there has been little systematic analysis of whether the promulgation of these laws has been worth the effort. What has the impact been? Have the costs of regulating microfinance institutions (MFIs) been justified by the benefits for their clients and the general public? At the same time, regulatory impact assessment (RIA) as a method to measure the success of all types of regulatory reforms has grown in popularity both amongst policy-makers and researchers. These developments together - the growth in specific legal frameworks for microfinance and new research on regulatory impact assessment - provided a unique opportunity to develop and test an RIA methodology specifically tailored to microfinance. The rationale-objectives-indicators approach used in this book has the potential to be widely applied for a wide range of studies assessing the ex ante or ex post impact of regulatory reform initiatives in microfinance.