The simple, one-step electrooxidation of pyrrole from an organic solvent on a platinum electrode results in the formation of a flexible, metallic polymer. The black films stripped from the electrode are found to be unchanged under ambient storage and thermally stable to temperatures exceeding 300 °C. They are space filling, unlike the fibrillar (CH)x and show considerable disorder. The room temperature conductivity ranges from 10-100 (ohm cm)-1. The thermopower is small and positive, decreasing linearly with decreasing temperature, consistent with p-type metallic conduction. The very small Hall constant is anomalous in both sign and magnitude. © 1980.