In the last two decades there has been seen a great improvement in the field of AI especially in the area of facial recognition systems. This book has the main purpose of analyzing the specialized literature to identify the most relevant research(1) and to building an intelligent facial recognition software(2) that can efficiently detect the face of a person from a picture and validate if that person exists in a given database for the purpose of authorizing its access. The obtained software brings contributions to the real world for a variety of sectors, including the financial one, by supporting organizations to consolidate its access control by proposing an affordable, reliable, efficient, and more secure way of authorizing its employee's access in buildings and rooms with limited access. The manuscript proves that the capabilities of facial recognition systems are almost unlimited, and its potential is truly great.