Many Swiss streams exhibit high levels of plant-protection product (PPP) inputs, with erosion and runoff being important entry paths. This article furnishes an overview of measures for reducing PPP inputs into bodies of water from arable land due to erosion, runoff and drainage, and provides an expert-based qualitative evaluation of these measures in terms of state of research, practical feasibility, acceptance, progress with implementation, and potential for reduction. The effectiveness of many measures is scientifically proven, and practical feasibility is also given in many cases. There is significant room for improvement in terms acceptance of the measures by farmers, and regarding implementation in particular. Whereas many of the measures have great potential for reducing PPP inputs in a specific location, only a few show potential for nationwide implementation. Consequently, the large variation in site factors across Switzerland means that reduction measures must be taken regionally and be adapted to the site in question.