A catheter with a mechanism for omni-directional deflection of a catheter shaft includes a shaft assembly and a controller. The shaft assembly includes a first tubular component that has a preformed curvilinear distal section, a second, substantially straight tubular component with a main axis and an outer shaft. The first and second components are configured for slidable movement therebetween while preserving common rotation so that when the second component is axially moved in a distal direction, the second component deflects the preformed curvilinear section towards the main axis while orientation of the outer shaft is preserved. The controller is configured to effect relative axial movement between the first and second components as well as to effect rotation of the first and second components (and thus also of the preformed curvilinear distal section) without any rotation of the shaft relative to the handle. Varying the deflection of the preformed curvilinear section in combination with variable rotational movement achieves omni-directional distal tip bending.