In this paper we present FINDS a training system for new forensic scientists and a prototype of a knowledge base system. This system is for pre-assessment and assessment of fibre evidence. The pre-assessment and assessment involves uncertain reasoning through a Bayesian network for fibre transfer, persistence and retrieval. FINDS also provides support in the training of new forensic scientists on decision making under uncertainty. This training is required when a forensic scientist needs to decide whether a forensic fibre analysis is cost-effective for clients such as the police and law firms.