Sundern is situated approximately 10 km (6 mi) south-west of Arnsberg. Around Sundern extends the nature park Homert which attracts tourists, many from the Netherlands. Winter tourism is also substantial, primarily in the municipality Wildewiese with its skiing area. The Sorpesee, an artificial lake, is used by watersportsmen, campers and fishermen.
The main industries of Sundern are several domestic and industrial lighting companies, household appliances and packaging businesses.
SEVERIN Elektrogeräte GmbH has its headquarters in Sundern.