Two different replacement investment strategies, derived from two case studies within Swiss Forest Ecosystem Research, are assessed for sustainability in terms of dematerialization and low rebound effect. The so-called broad strategy uses a broad focus on the whole replacement investment field. It includes analysing and optimising all processes and workflows and then choosing the appropriate hard- and software components. It is the mainstream replacement investment strategy nowadays. The narrow strategy has the goal of keeping the old, possibly already optimised workflows and processes and using modern "dematerialised" devices. The advantages of this strategy are a low or no rebound in combination with a considerable dematerialization effect. This approach is often ignored in today's IT investment decisions. The two strategies can be combined to find an optimal, project-specific solution.