The determination of anisotropy in a phreatic aquifer by means of a pumping test can be carried out, under given conditions, with common analysis methods. This paper develops and applies an amended method based on a technique proposed by Boulton (1970). This new method enables a quick, simple determination of vertical hydraulic conductivity, given drawdown data from a pumping well and at least one observation well, that is applicable to confined phreatic aquifers.