The neutrino evolution is a long-standing problem in particle physics since many decades ago. In the 3-neutrino mixing framework, the description of the evolution depends on two different wavelengths ∆m^{2}_{21} and ∆m^2_{31}, three mixing angles θ_{12}, θ_{13}, θ_{23} and a complex phase δ_{cp} that quantifies the CP-violation in the leptonic sector. The goal of a global fit is to determine those six parameters by combining the last data set. After a brief discussion about the description of the neutrino evolution, I am going to present the main problems in the neutrino oscillation experiments and their impact on the results of the global fit. In the conclusions, I am going to present the determination of the oscillation parameters with the data up to January 2018. The results are based on NuFit 3.2