Soft tissue sarcomas are one of the most common malignancies of the cutaneous and subcutaneous tissues. Traditionally, soft tissue sarcomas have been considered as a collection of different histologic subtypes with similar biologic behaviour; invasive and predisposed to a high local recurrence rate following conservative surgical resection; and that treatment with radiation therapy improves local tumor control and chemotherapy improves survival time (in dogs with grade III soft tissue sarcomas). However, recent studies have cast doubt on the similarity of the biologic behaviour of different subtypes of soft tissue sarcomas and the local aggressiveness of soft tissue sarcomas, especially in particular anatomic locations. Furthermore, we will discuss the lack of published studies supporting the use of either radiation therapy or chemotherapy in the management of incompletely excised or grade III soft tissue sarcomas, respectively.