In recent years, there has been a sustained interest in vascularization processes. Much, if not all, of the work has included the concept of new vessel morphogenesis. Surprisingly, most of the work has not addressed developmental mechanisms directly, but rather as an offshoot of a disease process, wound healing process, or from the perspective of inducing vessels in an ischemic site. One theme has dominated the various studies on capillary or endothelial tube morphogenesis-integrin-mediated cell behavior. Integrin biology impacts virtually every known step of nascent vessel formation. In this review article, we attempted to summarize key findings from the viewpoint of developmental biologists/morphologists. We also attempted to summarize and contrast data obtained using integrin gene ablation approaches in mice with other experimental systems. It is hoped this review will provide a distinct cell biological perspective to vascular scientists from the clinical, molecular, and tissue engineering communities.