Irregularities have appeared through almost the entire detectable range of hemopoiesis, from stem cells to functional mature populations in several models of murine lupus. The documentation of widespread abnormalities in many cell lineages implies the existence of a common, defective ancestor, perhaps the pluripotential hemopoietic stem cell. Of major concern are the microenvironmental pressures that may be driving hemopoiesis to its pathological state. The studies to date have not isolated the hemopoietic components from their cellular surroundings. Hence, the existence of a primary defect in any particular cell compartment is as yet an unanswerable point. Additionally, maternal forces must be considered as environmental factors whose consequences may extend into postnatal life. Also, the possible existence of hemopoietic cell influences on their environs are always present, creating a cellular ecosystem. As new techniques become available for the analysis of these cells, such as long-term cell culturing, more complete pictures of these murine models of autoimmunity will emerge.