Aya Expanse is an open-weight research model with advanced multilingual capabilities. It merges high-performance pre-trained models with one year of research from Cohere For AI, including data arbitrage, multilingual preference training, safety tuning, and model fusion. This powerful multilingual large language model serves 23 languages, including Arabic, Chinese (Simplified and Traditional), Czech, Dutch, English, French, German, Greek, Hebrew, Hindi, Indonesian, Italian, Japanese, Korean, Persian, Polish, Portuguese, Romanian, Russian, Spanish, Turkish, Ukrainian, and Vietnamese.