HVAC (pronounced either "H-V-A-C" or, occasionally, "aitch-vak") is an initialism/acronym that stands for "heating, ventilating, and air conditioning". HVAC is sometimes referred to as climate control and is particularly important in the design of medium to large industrial and office buildings such as sky scrapers and in marine environments such as aquariums, where humidity and temperature must all be closely regulated whilst maintaining safe and healthy conditions within. In certain regions (e.g., UK) the term "Building Services" is also used, but may also include plumbing and electrical systems. Refrigeration is sometimes added to the field's abbreviation as HVAC&R or HVACR, or ventilating is dropped as HACR (such as the designation of HACR-rated circuit breakers).

Kathryn Hagen has contributed to Fashion Illustration for Designers as an author. "Kathryn Hagen" is an artist and a full professor of illustration, drawing, and cultural studies at Otis College of Art and Design in Los Angeles, where she has taught for the last twenty years. A graduate of Parsons School of Design in Fashion Design, she also has a BFA and MFA in Fine Arts in painting and sculpture from Otis. This course is designed to draw professional designers, as well as those who are just keen on fashion design.