The purpose was to determine whether traditional learn-to-swim progressions, leading to a 10-m front and 10-m back swim, were developmentally valid for children with physical disabilities. Forty children (22 boys, 18 girls) ages 5 to 12 years participated. They were classified according to disability type, functional sport classification, mode of ambulation, and flotation device use. Developmental validity was assessed by testing the children on rhythmic breathing, front float, front glide, front swim, back float, back glide, and back swim. Each skill was deemed successful if the child accomplished all performance criteria of that skill. Atypical progression was evident if a child performed a skill without the ability to perform skills previously listed in that progression. Atypical progression occurred in 32 (80%) children in the front skills and 22 (55%) in the back skills, which indicates that the traditional learn-to-swim progressions for both the 10-m front swim and the 10-m back swim were not developmentally valid for most children with physical disabilities in the conducted research.