This report attempts to determine the suborbital private space flight market structure. It contains a critical analysis of the current forecasts of market demand, and in particular, the Futron market surveys. Market supply is also analyzed, with a focus on Virgin Galactic. A Microsoft Excel based Suborbital Supplier Technical Cost Model (SUBSTEC) has been created for the primary purpose of determining the minimum efficient scale and profit maximizing quantity of a suborbital flight service provider. The methodology of this cost model is explained, and the results are critically analysed.