The provision of a shrouding duct for an aerovalved pulse combustor is, for some applications, essential in that it permits the combustor to both entrain a secondary airflow and operate with a single air inlet and with a single outlet. Results are summarised representing extensive testing of pulse-combustor shroud ducts showing that the geometrical configuration of a shroud duct is relatively critical to performance. A stagnation pressure gain of 4% of the compressor absolute delivery pressure has been demonstrated on a small, low pressure ratio, gas turbine employing a shrouded, aerovalved, pulse combustor. The loadings of shrouded pulse-combustors are compared with loadings of steady-flow combustors. It is shown that when the core pulse combustor is of the single inlet type, shrouded pulse-combustors have relatively low volumetric loadings although it appears to be possible to ameliorate this by substituting a multiple-inlet pulse-combustor for one of the single inlet type.