Working activities are always productive in more than one respect. Concrete or imaginary objects are converted into a product as a result of working activities and in perfonning the activities people are altered. The outcome may be positive, i .e . the task has been completed successful ly and people have developed their ski l l s or have found satisfac­ tion through working activities. However, the outcome of work may also fai l to meet the standards specified in the work assignment or a person 's state may take a turn for the worse in performing the task. Positive outcomes are not l ikely to be associated with the term "load", although meeting task demands is always taxing and requires effort, for demands are made on the abil ities and on the wil l ingness to dedicate these abil ities to the task. Thus, exposure to task demands does not necessari ly have to be con­ ceived of as a predominantly negative process, although it usually is. The term workload tends to be associated with decrements in performance or wi l l ingness to perform, or with the risk of impair­

ment of the wel l-being and health of the task operator. We wi l l adhere to this convention.