This technical paper provides information on methodologies for assessing adaptation needs and their application, drawing on the inventory, available on the adaptation knowledge portal, of methodologies for assessing adaptation needs related to action, finance, capacity-building and technological support in the context of national adaptation planning and implementation, as well as on submissions from Parties and observer organizations on developing and applying methodologies for assessing such needs. The paper contains key concepts and definitions, provides an overview of existing methodologies and related experience, analyses lessons learned, emerging good practices and gaps, and concludes with recommendations.