The paper describes a Swedish-language customization (S-CLE) of the SRI Core Language Engine, which has been developed at SICS from the original English-language version by replacing English-specific modules with corresponding Swedish-language versions. The S-CLE is intended to be used as a building block in a broad range of applications, such as data-base query system, machine translation systems, NL front-ends, speech-to-text/text-to-speech systems, and so on. Examples of the first two types of application already exist. The main part of the S-CLE is an extensive Swedish grammar that is compiled into parsing and generation modules. The grammar formalism is a type of unification grammar loosely based on Generalized Phrase Structure Grammar (GPSG). Generation is performed using the Semantic-Head-Driven algorithm. Analysis turns sentences into ``Quasi-Logical Form'' (QLF), a logical-form representation, while generation works in the opposite direction. Intermediate stages include processing of morphology, syntax and semantics. For knowledge-base applications, a separate module can convert QLFs into conventional scoped logical forms. After two-and-a-half years of work (approximately 45 person months), the first prototype system has a vocabulary of about 1900 words and covers a fairly broad range of possible grammatical constructions. Based on our experience in this project, we present in this paper detailed arguments to support the claim that customization of an English-language NLP system is a highly cost-effective way of constructing Swedish language systems with corresponding functionality.