The first federally-funded meeting on tissue engineering was in 1988. In this and subsequent meetings, the fields of tissue engineering and regenerative medicine (TERM) have been described as having the potential to revolutionize clinical approaches to the replacement, reconstruction or regeneration of organs and tissues. While TERM research has resulted in new patient treatments, the broad impact on clinical practice envisioned has not been achieved. The development of new TERM therapies that have significant clinical impact requires the ability to control vascularization, the process of new vessel assembly. The circulatory system plays a number of vital roles in regenerating and functioning tissues. It supplies oxygen and nutrients, removes wastes and is a source of multiple cell types required to respond to changing physiological conditions. For nearly every TERM application, the ability to enhance, regenerate or engineer new tissues requires spatial and temporal control over the process of vascularization. While vascularization is being studied in a number of physiologic and pathologic processes, TERM applications present distinct challenges. For example, unique microenvironmental conditions result from biomaterial and cell combinations used in TERM applications that are not encountered in any other system. In addition, clinical applications require vascularization of large tissue volumes within time frames that are much lower than those found during vascularization in development and typical physiologic processes. These requirements place significant constraints on the design of TERM therapies--Provided by publisher.