A survey of the MHO activity observed in both the ohmic and early radio frequency heated phases of the JET project is presented. The activity or its absence, during the initial current rise phase, flat top and current fall phase has been investigated. A study of disruptions both at the density limit and at low q has also been made. Some comparisons with linear and nonlinear 2D resistive instability calculations are presented. During the initial current rise phase mode activity can be quite complex. During the flat top phase the activity can be absent even at low q. Disruptions occur with primarily m = 2 precursors which slow down whilst growing and lock before the disruption. Internal disruptions (sawteeth) are observed on the internal coils. Modes with more than 1 helicity are usually present. At least 2 toroidal mode numbers are present and for a single toroidal mode number, the presence of current perturbations on more than 1 rational q surface is deduced.