Factors affecting the design and performance of digital recording heads are discussed with reference to multitrack write/read heads for use with thin high-coercivity disc media. Account is taken of the flux leakage paths round each ferrite core to calculate the core efficiency and crosstalk from an adjacent core. The efficiency for a core with permeability = 1000 is about 20% less than obtained by neglecting leakage. Formulae are given to find the minimum recording gap, leakage permeances, peak output, and write current. Values are plotted versus gap length and depth, pole-tip angle, back gap, core pitch, and permeability.