Charitable purpose test: commercial activities disqualify organizations from exemption when advancing objects of general public utility. The proviso to section 2(15) excludes from charitable purpose any advancement of objects of general public utility that involves trade, commerce or business activities or rendering services related thereto for consideration; the proviso does not affect relief of the poor, education or medical relief, which remain charitable even if incidental commercial activities are undertaken, provided the business is incidental to the objectives and separate books of account are maintained.