Professionals in the field work similarly to account managers or sales engineers, in that they have a high level of technical expertise and focus on customer satisfaction to ensure relationships are maintained.
The SE is not only familiar with traditional sales actions, but also the technical aspects of the product being sold, how it works, what it works with, and what solutions are best for any given problem- including the solutions competitors offer.
Large companies tend to break their sales departments into two main groups; those who help generate new business, also referred to as business development representatives, and those who help keep existing customers happy so they renew or continue to purchase additional products or services, generally called account managers or account executives.
Professionals in partnership management, also referred to as strategic partnership management, strategical alliance, and similar terms, help their companies grow by cultivating mutually-beneficial partnerships with other organizations.
Oftentimes, corporate development gets lumped in with things like corporate strategy, development, or finance, and while all these professions are dedicated to helping companies grow, corporate development managers tend to focus mostly on creating strategic partnerships with other companies and mergers and acquisitions.