Innovation research has resulted in various methods to classify service innovations, which primarily feature either the degree of change or type of change. This paper develops a novel classification scheme, based on a four-dimensional view of innovativeness. The classification scheme simultaneously concerns both the degree and type of change in service innovations. A multiple-case study is conducted in the empirical settings of theme parks and airlines, with 11 service innovation projects situated in Walt Disney World, Singapore Airlines, or China Eastern Airlines. Following the proposed scheme, the 11 cases are analyzed and classified into four dimensions: environment-, technology-, market-, and organization-dominant service innovations. The scheme offers academics and practitioners an integral understanding through four dimensions that build on each other.