INTRODUCTION The examples in the Item provide insight into the application of Data Item 96002 (Reference 2) for the design of both external and internal Geneva mechanisms. Aspects of the design process include determination of the following:- (i) geometric relationships between the wheel@ crank and roller (or pin)@ (ii) wheel motion@ (iii) forces and torques@ (iv) contact stress@ (v) lubrication film thickness and regime (if applicable) and (vi) roller performance (if applicable). Data Item ME3 (Reference 1) presents the underlying theory used to analyse a Geneva mechanism and identifies the interdependent relationships between its design parameters. Analysis of the mechanism is carried out using the ESDUpac A9611 computer software@ described in Data Item 96011 (Reference 3). Example 1 describes in detail how the ESDUpac A9611 software is used to analyse a typical external Geneva mechanism in which the designer has certain timing and spacing constraints that must be satisfied concerning the machine in which it must operate. Although the example includes consideration of a realistic design problem@ the primary objective is to illustrate the procedures necessary to use the software effectively. The distance between the crank and wheel shaft@ the operating speed of the crank and the load to be driven by the output shaft are all fixed. The two-stage process by which a new design is modelled using the software is described and the performance of the mechanism is assessed from the information generated by the software. Example 2 describes the analysis of an internal Geneva mechanism capable of fulfilling the same functional requirements of the mechanism as those of Example 1@ using the same roller bearing@ lubricant and materials. A comparison of the relative merits of the two types of Geneva mechanism is made. Example 3 demonstrates the most desirable strategy to be used when designing an external Geneva mechanism where only the operating speed of the motor@ the driven load and the minimum dwell time required for the operation of the machine are specified. The procedure is described whereby the designer fixes the diameter of the wheel and the dependent distance between input and output shafts together with the crank dimensions is to be found. The example includes an assessment of the interdependent effects on the performance of the mechanism resulting from different combinations of the numbers of slots in the wheel and the bearing size. Replacement of the roller by a pin is considered. A number of acceptable design solutions are considered and the most cost effective design is identified. Example 4 demonstrates the analysis of an external Geneva mechanism in which the crank angular velocity varies during each rotation and the external torque driven by the mechanism is not adequately represented by any of the (four) standard models provided in the ESDUpac A9611 software. The mechanism is analysed for a nominally constant angular velocity and the results are compared with an analysis of the same mechanism operating with a sinusoidal variation of the nominal crank speed. The latter analysis shows that the contact stress exceeds the stated limit. A method to identify the dominant factor causing the high contact force is described and methods of reducing the contact stress considered. Example 5 shows how the size of a Geneva mechanism capable of performing a series of tasks within a packaging machine is minimised@ while ensuring that the specified performance targets are met. The effect of the offset mass centre of the Geneva wheel on the performance of the mechanism is considered. Example 6 describes how transient effects may be analysed as part of the design of a Geneva mechanism. The mathematical approach necessary to develop a representative external crank motion data file is described. Four analyses are carried out for different combinations of start-up time and initial crank angle that might be encountered during the start-up of an external Geneva mechanism required to operate at constant speed.