This document outlines initial criteria for best practices in mainstreaming disability in development based on the UN Convention on the Rights of Persons with Disabilities (CRPD). It discusses mainstreaming as including persons with disabilities in all development efforts through both disability-specific and inclusive actions. The document presents criteria such as non-discrimination, participation, accessibility, capacity building, data collection, and partnerships to evaluate best practices. It aims to provide case studies illustrating these criteria from different regions and themes of inclusive development.