Adult stem cell research is one of the most dynamic and fast growing fields of our time. Investigating how organs maintain and repair themselves has led to the discovery of cell populations throughout the body that hold immense regenerative capacity. For a long time, research on adult stem cells has been held back by the inability to grow and study these cells in vitro. This limitation has finally been overcome with the development of organoid technology, a system that enables us to grow single adult stem cells into self-organizing miniature organs. These organoids perform many functions of their parent tissue and are excellent tools to study organ regeneration, organ function and disease development. This presentation provides an overview of the many contributions the team around Hans Clevers has made to the development of organoid culture and delves into applications of the technology in disease modeling, pharmacological screening, regenerative medicine and cancer research.