As technology increases and performance requirements continually tighten, the cost and the required precision of assemblies increase as well. Due to the variations associated with manufacturing process, it is not possible to attain the theoretical dimensions in a repetitive manner. It causes a degradation of functional characteristics of the product. In order to ensure the desired behavior and the functional requirements of the system in spite of variations, the component features are assigned a tolerance zone within which the value of the feature i.e. situation and intrinsic lie. Therefore, tolerance analysis is a key element in industry for improving product quality and decreasing the manufacturing cost. In addition, it participates to an eco-aware attitude since it allows industrials to manage and reduce scrap in production. Tolerance analysis concerns the verification of the value of functional requirements after tolerance has been specified on each component. The main objective of the AHTOLA proposal is to develop hybrid approaches for a large scope of product behavior models. Those approaches have to be based on: - worst case analysis approaches like Solution Space Exploration based on Interval Reduction Methods (Numerical Quantified Constraint Satisfaction Problem - Box consistency, …), Solution Space Exploration based on Evolutionary Methods (Genetic algorithm, …), and … to assess the worst gap configurations regarding to the assemblability and the functional requirements ; - probabilistic approaches like Simulation based method (Monte Carlo Simulation …), Most probable point based methods (FORM-SORM), Meta-modeling based method (Kriging …), to estimate the probability of system conformity based on the process capabilities or statistical distributions of component deviations.