Recent surveys of the Galactic plane have identified large populations
of candidate young massive protostars. However, we have a very poor
understanding of the actual evolutionary status of these sources. The
SED based classification schemes used for nearby low mass objects are,
alone, inadequate at the large distances of these high mass objects
which are embedded in inhomogeneous environments. This presentation will
discuss an ALMA Cycle 3 project which has provided the first
comprehensive, systematic, high angular resolution survey of the
chemical (and physical) properties of a well selected sample of 39 young
high mass embedded sources. This survey has observed a single frequency
setting in Band 6 at ∼ 1” resolution to study a range of organic
molecular species which trace the evolution of the circumstellar
material as a protostar initially heats its environment. The column
density and excitation temperature of these species, together with the
dust continuum emission, will be used to study how the properties of the
circumstellar molecular gas change with source luminosity, spectral
energy distribution and other properties with the goal of identifying
evolutionary trends. With the recent delivery of the data for all 39
sources, this presentation will provide an overview of the survey and
its initial results.