Definition of services under GST clarifies taxable activities, key exclusions and treatment of money, securities and support services. The document defines services for GST as any activity for consideration by one person for another, excluding certain transfers of goods or immovable property, transactions solely in money or actionable claims, and employee services; it includes facilitation of securities transactions and conversion of money when separately charged, explains broad meanings of 'activity' and 'consideration', describes deeming rules for establishments and agencies, and defines 'support services' as outsourced infrastructural and operational functions while excluding non substitutable sovereign functions.