Natural language generation is now moving away from research prototypes into more practical applications. Generation functionality is also being asked to play a more significant role in established applications such as machine translation. In both cases, multilingual generation techniques have much to offer. However, the take-up of multilingual generation is being restricted by a critical lack both of large-scale linguistic resources suited to the generation task and of appropriate development environments. This paper describes KPML, a multilingual development environment that offers one possible solution to these problems. KPML aims to provide generation projects with standardized, broad-coverage, reusable resources and a basic engine for using such resources for generation. A variety of focused debugging aids ensure efficient maintenance, while supporting multilingual work such as contrastive language development and automatic merging of independently developed resources. KPML is based on a new, generic approach to multilinguality in resource description that extends significantly beyond previous approaches. The system has already been used in a number of large generation projects and is freely available to the generation community.