The managerial approach views marketing as a management science. It uses problem-solving to "develop an optimum offering of products, prices, promotion, and place (distribution)," according to the "Handbook of Marketing." A key feature of the managerial approach is that it began to move away from its economics foundations and instead introduced ideas from the new and emerging fields of sociology and psychology, which offered useful insights for explaining aspects of consumer behaviour such as the influence of culture and social class. It also placed an overt reliance on the quantitative sciences as means of knowing."