Different investigation techniques are described to measure transmissivity, saturated hydraulic conductivity (K), and/or intrinsic permeability (k) in laboratory and on field at different scales. Under transient conditions, storage coefficient and specific storage coefficient can also be deduced depending on the method used for interpretation of the test. Laboratory techniques include empirical relations based on grain size distributions, permeameters, and oedometers. On field techniques are discussed: slug tests, pumping tests, and other tests like Lugeon, Lefranc, Porchet, and also air permeameter measurements. More emphasis is given on pumping test interpretation methods since they are the most common methods for hydraulic conductivity measurements. These include the steady-state and transient methods for unconfined and confined aquifer conditions: Thiem's and Dupuit's method for steady-state, the Theis, Cooper-Jacob, and Birsoy-Summers methods for transient conditions, recovery methods, image well theory, and the Hantush and Neuman-Witherspoon methods. Dedicated features are also addressed as anisotropy, correction for partially penetrating wells, well-bore effects, and head losses.