Abstract Evidence is examined for double diffraction dissociation in the reactions π ±p → (3 π) ±(N π) + with (3 π) ± masses between 1.0 and 1.2 GeV at 16 GeV/ c incident beam momentum. The data considered are found to reveal: 1. (a) isospin zero exchange, 2. (b) the expected factorisation properties, 3. (c) a d σ/d t′ slope compatible with those deduced from single dissociation processes and elastic scattering, and (d) as shown by an analysis of D moments, (3 π) ± systems with the same typical spin-parity composition as observed in the diffractive single dissociation reactions π ±p → (3 π) ±p. Comparison of the 16 GeV/ c data with data of an 8 GeV/ c experiment indicate an almost energy-independent cross section for the process investigated.