In Fundamentals of Perspective 1: One-Point Principles and Concepts, the viewer is first introduced to the tools and definitions used in one-point perspective. One-Point perspective is demonstrated through a series of exercises indicating the relationship of the viewer with the picture plane and the object that is to be constructed.
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In Fundamentals of Perspective 2: Two-Point Principles and Concepts a series of two-point examples include measuring point perspective,  projecting from plans and elevations and repeating rectangles in foreshortened perspective are covered in detail. Gary also provides examples of how to correctly draw ellipses in perspective. Inclined planes are also demonstrated using auxiliary vanishing points and vertical vanishing lines.
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The exercises in Fundamentals of Perspective 3: Three-Point Principles and Concepts initially cover the primary concepts used in three-point perspective and then move on to discussing measuring points to construct an architectural object. Gary then demonstrates the concepts of plotting shadows from natural and artificial light sources in perspective before moving to the final lesson where he demonstrates how to plot reflections while transferring scale in perspective.
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This series provides a solid foundation for any artist looking to strengthen their comprehension of the principles and concepts of drawing in one, two and three-point perspective.