Business development entails tasks and processes to develop and implement growth opportunities within and between organizations. It is a subset of the fields of business, commerce and organizational theory. Business development is the creation of long-term value for an organization from and for customers, markets, and relationships (from https://en.wikipedia.org/wiki/Business_development). Understanding the needs of current and future customers should be the baseline for business development. There are two main dimensions of business development, exploitation of current resources (continuous improvements) and exploration of new value (disruptive business models).
See also the section dedicated to Business model aspects.