Children with Rett Syndrome (RS) have neuromotor impairments that impact their mobility. Poor hand function among children with RS limits the selection of an assistive device for ambulation. Purpose: The purpose of this case report is to describe the process of selecting an assistive device for a child with RS to promote ambulation. Method: This single subject case reports on a 5-year-old girl with RS at a suburban mid-western early childhood special education setting. Results: The child in this case was able to walk the farthest distances with a metal toy shopping cart and then with an anterior facing four-wheeled walker. Conclusion: The outcome suggests that physical therapists and health professionals caring for young children with RS consider using a metal toy shopping cart to establish and practice ambulation prior to selection of a longer term, adjustable anterior facing walker like the one in this case report.