The demand for non-standard custom fasteners is driven by increasingly complex engineering applications where off-the-shelf solutions are inadequate. This necessitates a rigorous design process tailored to unique functional, environmental, and integration requirements. This article outlines a systematic methodology for developing custom fasteners, focusing on the critical stages: requirement definition, conceptual design, detailed engineering analysis, prototyping, validation, and final specification. Crucially, it details the determination and justification of key technical parameters,