When you:

• wanted to check that the person whom you wished to answer the questions had actually answered the questions;

• have sufficient resources to devote to delivery and collection and the geographical area over which the questionnaire is delivered is small;

• can use field workers to enhance response rates. Delivery and collection questionnaires have a moderately high response rate of between 30 and 50 per cent compared with 30 per cent offered on average by a postal questionnaire;

• are delivering a questionnaire to an organisation’s employees and require a very high response rate. By delivering the questionnaire to groups of employees in work time and collecting it on completion, response rates of up to 98 per cent can be achieved.