Cross-language information retrieval (CLIR) aims to find relevant documents that are written in a different language than the query. When there is not enough relevant information in the language of the user, the user may be interested in using CLIR to find more information originally written in other languages. In this talk, we will describe the problems of CLIR and its differences with general the machine translation task. The traditional approaches will be described, namely the ones based on machine translation, bilingual dictionaries and parallel and comparable texts. Although reasonable effectiveness can be obtained using these approaches, problems remain. We will further analyze the remaining problems and describe the current efforts to solve them. Finally, we will show that the approaches developed for CLIR can be adequately used for other IR tasks such as monolingual IR. This talk will provide a general introduction to the area of CLIR and suggest some interesting research problems for the future.