Massive stars begin their lives in cold, dense cores which are much more massive than the stars which form in them. We summarise the results of a program to find the earliest examples of massive star formation, and to examine the evolutionary sequence of events that occurs as such a star begins to form and heat its surroundings. Methanol maser emission has proved to be a particularly potent tool to locate such cores, though there are also clearly many massive cores which do not exhibit such

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... r emission. Our program began with a survey for 6.6 GHz methanol maser emission, but expanded to include dust continuum surveys in the mm and sub-mm, a survey for hot molecular cores associated with 'isolated' masers through mmline CH 3CN emission, and follow-up probing of some cores through sub-arcsecond, diffraction limited observations in the mid-IR. This program is outlined below.