This Guide to Effective Indigenous Involvement in Federal Impact Assessment (the guide) is intended to enhance the capacity of Indigenous Nations to effectively engage in the new federal impact assessment (IA) process. It is also intended to support Indigenous Nations’ active involvement as key players, rather than mere participants, in the new IA process. This guide is written for technical staff and leadership of member Nations of the First Nations Major Project Coalition (FNMPC), as well as of any other Indigenous Nation, who are looking for ways to make the most of the new IA process and gain a greater degree control when major projects are proposed within Nations’ traditional territories. Ultimately, the guide seeks to empower Indigenous Nations to take advantage of new opportunities that exist within the new IA process, supporting effective involvement and advancing the rights and interests of Indigenous Nations within the process. The guide is organized as follows: Part I introduces the FNMPC and provides the background and context of the guide. Part II reviews the new IA process and highlights key changes from the previous IA process that are relevant to FNMPC members. Part III presents and discusses tools to help Indigenous Nations realize the opportunities for effective Indigenous involvement in the new process, including how to successfully prepare for, and contribute to, an IA. Part IV outlines opportunities through the FNMPC for gaining additional technical support, and identifies areas where further guidance development related to IA is expected in the coming months and years.