The development landscape has changed significantly over the last few decades, becoming increasingly complex. Many of the issues we face today such as climate change, poverty and conflict, call for a new way of doing business. This guide shows leaders and development practitioners how to navigate this complexity and manage their initiatives/organizations successfully towards sustainable development impact. The Managing for Sustainable Development Impact (M4SDI) approach presented in this guide is an integrated, resultsoriented management approach, which can be used across a range of sectors and domains in a variety of contexts, and aims to contribute towards the Sustainable Development Goals. It addresses some of the most pressing concerns, such as engaging primary stakeholders, designing effective strategies and related M&E, focussing on capacity development, and responding to change in a complex context. Key features of M4SDI include its people-centred approach and how it seeks to integrate planning, monitoring and evaluation processes. This guide builds on the earlier work of Irene Guijt and Jim Woodhill in the 2002 IFAD publication Managing for Impact in Rural Development: A Guide for Project M&E, and incorporates the insights and feedback of CDI colleagues, partners and over 800 practitioners who have been trained in using the approach in English, French and Spanish. We all have a role to play in contributing to a more sustainable world and we hope this guide will inspire and spur you on to do your part.