Abstract. Digital libraries are increasingly relying on distributed services to support increasingly complex tasks such as retrieval or preservation. While there is a growing body of services for migrating digital objects into safer formats to ensure their long-term accessability, the quality of these services is often unknown. Moreover, emulation as the major alternative preservation strategy is often neglected due to the complex setup procedures that are necessary for testing emulation. However, thorough evaluation of the complete set of potential strategies in a quantified and repeatable way is considered of vital importance for trustworthy decision making in digital preservation planning. This paper presents a preservation action monitoring infrastructure that combines provider-side service instrumentation and quality measurement of migration web services with remote access to emulation. Tools are monitored during execution, and both their runtime characteristics and the quality o...