In the past few decades, the ways in which we look at heritage, and what the idea of heritage entails, has evolved and changed dramatically. We are constantly working on coming to grips with its complex nature and its multi-facetted ramifications. The aim of this thesis is to explore future strategies for museums in their continued work with collecting, preserving, and managing our cultural heritage in order to become more sustainable institutions. Furthermore, the thesis investigates historically what has led to the current crisis of accumulation and a profusion of heritage, with the intention of substantiating and providing background to the alternatives presented for the future of museum collections. In addition to a literature review of past research on the subject, an analysis of collection management plans and conducted interviews from four museum institutions in Sweden was carried out. The participating institutions were the National Historical Museums, Stockholm City Museum and Medieval Museum, the National Museums of World Culture and Museum Gustavianum. The results find that a rapid expansion of the concept of heritage to incorporate a large range of new forms of material and immaterial memory, alongside an exponential growth in the number of objects and places that are identified, collected and exhibited as cultural heritage, has contributed to a crisis of accumulation. Globalization as well as a large production growth of material things have also been assisting factors. The five strategies put forward to help museums become more sustainable institutions are: identify what your museum needs to focus on, now and in the future; if your museum does not have a collections management plan it is vital to write one; implement deaccessioning as an active collections management tool; with culture in the forefront, strive for sustainable development regarding both collections management and other museum activities; and collaborate and cooperate more with various interested parties to benefit collections development. This is a two years master’s thesis in Museum and Cultural Heritage Studies.