  We present the results of short baseline interferometry observations at
submillimetre wavelengths, using a two-element interferometer comprising the
JCMT and CSO, of circumstellar discs around young YSOs. We model data for the
Class 0 protostar IRAS03282 and the Class I protostar L1709B with discs and
compare them with previously published results. We find evidence for the ratio
of the disc mass to envelope mass to increase as the objects evolve.
