From the early 20th century onwards, artists have employed plywood as a cheaper, more uniform, and versatile replacement for solid wood in panel paintings. Now, a half century or more later, as these modern substrates begin to deteriorate, conservators are faced with novel problems. These problems became evident in a group of paintings by the American artist William H. Johnson (1901-1970) who executed several paintings on plywood sheets between 1939-1944. Circumstances led to some of his paintings being abandoned for approximately 10 years. For some of this period, the paintings were exposed to the unregulated outdoor environment, resulting in gross delamination, buckling, and fracturing of the plywood laminae. A planned exhibition at the National Museum of American Art and the Conservation Analytical Laboratory of the Smithsonian Institution to explore treatment options. Two options for the treatments were to reintegrate the existing artifact as a whole, or to remove the lamina bearing the paint layer. Discusses the ethical and technical issues surrounding the artifacts and their treatments, reviews the models for each of the major options and subsequent variants considered, and illustrates the treatments as they were finally executed. -- AATA