This article describes how to establish a primary tissue culture, where cells are taken directly from an organ of a living animal. Cardiac cells are taken from chick embryos and transferred to culture dishes. These cells are not transformed and therefore have a limited life span. However, the unique characteristics of cardiac cells are maintained and students are able to see that living tissue can continue to survive in a differentiated state, even outside of the whole organism. Cardiac cells have a unique feature--they are able to contract without input from the nervous system. Each cell contracts (or beats) at its own inherent pace (Johnson, 2003). In vivo, when the cells become attached to one another, they will communicate and will synchronize their beating (Johnson, 2003; Jongsma et al., 1987). In this laboratory exercise, the student can observe the beating of cardiac cells--individually and in unison. (Contains 3 figures.)