Guidelines on asthma management have changed considerably in the last two decades. Patient education has gained in popularity and especially asthma self-management training is thought to be essential in the treatment of adult asthma. Since 1989 many researchers have added self-treatment guidelines to self-management programmes and several studies have found improvements in health outcomes, such as lung function, quality of life, use of health care facilities and asthma symptoms. However, because of the lack of proper control groups, it is not clear whether this has to be attributed to self-treatment guidelines or to, for example, more education or more medical attention. The only two studies that were placebo controlled did not show an effect of self-treatment. To assess the added benefit of self-treatment guidelines to a self-management programme, randomized 'placebo' controlled trials of sufficient size with sufficient follow-up time are necessary. The only difference between intervention and control groups should be guidelines for self-treatment.