An estimated 7.3 million people die from coronary heart disease each year, according to the recent report of the World Health Organization. In the hope of true regeneration of the infarcted or failing heart, stem and progenitor cells from various sources have gained massive attention in recent years. Data from animal and human studies have been conflicting, and cell type and application varied significantly across all protocols. It now has become clear that many details of cardiac cell therapy remain to be elucidated. In this context comprehensive in vivo imaging methods are essential tools to evaluate mechanisms of cell engraftment and function. In the present review we summarize current imaging modalities for tracking transplanted cells in animals and humans including most recent developments in the field.