Simmons produces very few traditional watercolors anymore; his best work embraces an oil painter's sense, combined with the striking effects that only water-based media can achieve. When painting, he strives to compose either an abstract perspective of the real, or an engaging interpretation of the unreal.

Nicholas has studied with many watercolorists, including Barbara Nechis, Valfred Thelin, Nicholas Reale, Claude Croney, Wayne Sessions, and Al Brouillette. Mr. Simmons' work is in many private and corporate collections in Iowa, the Permanent Collection of the Cedar Rapids Museum of Art, and private collections throughout the United States and abroad. His major influences are the paintings of John Singer Sargent, Joaquin Sorolla, Andrew Wyeth, and the prints of Robert Motherwell, and Mauricio Lasansky.