Careful observation while problem solving an individual case of pediatric eczema using the engineering method led to a framework by which others could carry out similar environmental problem solving to alleviate their own individual cases of eczema and related allergy problems. The resulting heuristic, published on a web site in 2004, has been updated with community- and web-based user experiences to form a reliable resource. Understanding the effect of modern syndets on skin-barrier function under normal household conditions was crucial to developing the heuristic and may explain the increasing prevalence of eczema in the industrialized world.