A study tour of water resource planning, development and management in Israel, France and United States has shown the need for geologists involved in groundwater hydrology to familiarize themselves with aquifer modelling and computer techniques. At many of the areas visited hydrogeological problems were being solved by use of complex mathematical expressions easily handled by computer. Advantages are that answers may be obtained using a minimal amount of data and by approximating parameters where these are unknown. After calibration of models, sensitivity tests can show whether or not actual field measurements are required which in many instances are time consuming and costly. Amongst other recommendations are the proposals that alternative methods to drilling be tried to obtain aquifer parameters e.g. use of tracers, chemical analyses and isotope measurements. Where drilling programmes are necessary, they should be vetted to see that maximum information is obtained for minimal cost. In addition, a review of the whole Departmental observation well network is suggested so as to achieve optimum benefits from a very time consuming but necessary undertaking. Future trips should be programmed so that an individual has more time in one particular organization and can work on a specific project. This is preferable to visiting a large number of organizations and talking with a number of specialists on unfamiliar subjects. There is often insufficient time to fully appreciate more detailed problems associated with each subject before moving on to the next locality.