Significance Echidnas are iconic egg-laying mammals threated by environmental changes. However, their cryptic lifestyle and Australia-wide distribution renders a citizen science approach the only feasible way to obtain continent-scale information. With EchidnaCSI (Conservation Science Initiative), we used a citizen science approach to learn more about echidnas, which is remarkably powerful and continually provides data and material for molecular and ecological research. Here, we describe and discuss the establishment and performance of EchidnaCSI, which has produced high-quality echidna-sighting data and fecal material. In addition, a survey of participants provides insight into the motivation and engagement outcomes in citizen science and conservation. EchidnaCSI demonstrates the enormous potential of citizen science to advance the data and knowledge base to enable echidna conservation outcomes.