Recognition of the importance of mental health practitioners’ enactment of ‘gender competency’ when working with men is growing. This article describes the development and theoretical background to a novel online training program for practitioners, called Men in Mind. The training focuses on men’s gender socialization, engaging male clients in therapy, and responding effectively to men’s depression and suicidality. The content of the training was derived from a comprehensive review of available literature, structured into modules with measurable learning outcomes via learning design principles. The training employed a range of andragogic principles and tools (e.g., character vignettes, reflective exercises). Plans for evaluation via a controlled trial, alongside scaling, and implementation are described.