In her book Fundamentals of Collection Development and Management (2nd edition), Peggy Johnson states that "collection development and management are the meat and potatoes of libraries. If you don't have a collection, you don't have a library."
As librarians here at LCC, collection development is part and parcel of our job. We select materials relevant to our respective subject assignments as well as determine items that need to be weeded from our collection. We have our liaison assignments across departments on campus where we can engage with our faculty to promote our collection and services.
This guide is for all of us who are doing the work of building our library collection in order to ensure that our materials are current and relevant for our students, faculty, and staff.
Collection management is an umbrella term under which collection development is subsumed. It covers decisions about weeding, retention, serials cancelation, storage, and preservation and the activities that form these decisions such as use studies and cost/benefit assessment.
Collection development covers several activities related to the development of library collections, including selection, the determination and coordination of selection policy, assessment of the needs of users, budget management, identification of collection needs, community and user outreach and liaison, planning for resource sharing, and e-resources contract review and negotiation.
Source: Johnson, P. (2014). Fundamentals of Collection Development and Management, 3rd ed. Chicago: American Library Association.