Essentially all newborns in the United States (about 4 million per year) and at least 30 other countries have blood samples obtained on filter paper cards for the purpose of screening for a number of metabolic and genetic diseases. To prevent morbidity, such as brain damage, from metabolic diseases such as phenylketonuria or congenital hypothyroidism, it is critical that the screening results be obtained in a timely fashion. A persistent and well-documented problem for the newborn screening programs has been the arrival of inadequate blood card samples at the testing laboratories. These result in expensive recall testing and introduce a dangerous delay in the diagnosis of disease. This project will develop an imaging based system for the evaluation of blood cards to determine if they are adequate. Use of such a system at a birthing center will allow for the immediate correction of the problem, saving health care dollars and preventing any unnecessary delay in the diagnosis of important metabolic diseases.