Despite large investments in drug development, the overall success rate of drugs during clinical development remains low. One prominent explanation is flawed preclinical research, in which the use and outcome of animal models is pivotal to bridge the translational gap to the clinic. Therefore, the selection of a validated and predictive animal model is essential to address the clinical question. In this review, the current challenges and limitations of animal models are discussed, with a focus on the fit-for purpose validation. Moreover, guidance is provided on the selection, design and conduct of an animal model, including the recommendation of assessing both efficacy and safety endpoints. In order to improve the clinical translation, the use of humanized mouse models and preclinical applications of clinical features are discussed. On top, the translational value of animal models could be further enhanced when combined with emerging alternative translational approaches. Read more. . .