As a rule variable aspects of problems are determining factors in research projects in the field of market, opinion and social surveys and it is necessary to proceed with an eye to the variability in method and to the target groups in different districts. Apart from this the scope of questionnaires and the level of difficulty of the interview vary, again necessitating the services of interviewers with corresponding variable qualifications. Inevitably the costs and expenses incurred in carrying out research projects of this kind are bound to vary. Consequently it is at present still not possible to issue price lists for this kind of service, although these would be desirable from the customer's standpoint. The costs of each research project must be calculated on an individual basis by the organisation whenever an enquiry is received, taking into consideration the special circumstances and the task in hand in accordance with a plurality of factors. To ensure a really exact calculation about 40 different factors have to be borne in mind. When enquiries are directed to market research organisations, it is therefore advantageous if the maximum possible amount of such detailed information is available as will assist through study in arriving at a calculation. Not all clients will have at their disposal adequate expert knowledge in the field of market research that will enable all factors in calculation to be predetermined with exactitude. Project leaders of the organisations approached will gladly fill in the missing data. But perhaps the client may be in position to indicate some more factors by making use of the catalogue of questions. On perusal of the calculation sheet anyone can see that the calculation of research projects demands very careful examination and a corresponding amount of time, as otherwise correct estimates cannot be made.