A method of selecting a site for one or more retail units uses a database of information on existing units in a chain, including store sales or profits, site characteristics available from various databases, and information on marketing expenditure in the relevant market. Sales of potential new units are forecast abstracting from advertising efforts. Thus, potential profit characteristics of a site can be evaluated without regard to existing advertising programs. This corrects a major problem with existing approaches; site decisions can be made simultaneously with marketing allocation decisions.