This study explores Indigenous leadership within Latin American communities, specifically the Maya-Mam and Xinka communities in Guatemala. The research involves a multi-phase mixed-method grounded theory approach to understand Indigenous leadership competencies and their practical implications comprehensively. The initial phase includes qualitative case studies that examine perspectives from Indigenous leadership experts and non-Indigenous-based theories to develop an understanding Indigenous leadership, which guided the following phases. The subsequent phases delve into the specific Indigenous communities of Maya-Mam and Xinka using a grounded theory approach. The second phase investigates Maya-Mam Indigenous leadership competencies through fieldwork in San Marcos and Huehuetenango, while the third phase explores Xinka leadership competencies through interviews in Jutiapa, Cuiliapa, and Chiquimulilla. These phases provide valuable insights into the complexities of Indigenous leadership within these communities. The final phase focuses on developing and validating a scale that measures Indigenous leadership competencies among the Maya-Mam and Xinka communities. This scale includes service, mediation, Indigenous values, and experience, comprehensively measuring Indigenous leadership competencies. This study aims to contribute to the existing literature by shedding light on Latin American Indigenous leadership and offering practical implications for development programs. The study aims to bridge the knowledge gap and foster cultural awareness in Indigenous leadership, promoting collaboration and inclusivity.