Irritant contact dermatitis is the most common form of contact dermatitis, and yet is often overlooked. Recent progress in understanding the pathogenesis has reignited the interest of clinicians in this area of dermatology. Irritant contact dermatitis is not a homogenous entity, but rather a number of subtypes contributing to different clinical presentations. The diagnosis of irritant contact dermatitis is often clinical, and may only be possible after the exclusion of allergic contact dermatitis with patch testing. There is no readily available diagnostic test. There is an incomplete understanding of the factors which lead to the development of cumulative irritant contact dermatitis and persistent postoccupational dermatitis. We have used the experience from our tertiary referral occupational dermatology clinic to illustrate various aspects of irritant contact dermatitis, and to highlight the difficulty sometimes encountered in making this diagnosis. We believe that increased awareness of the often pivotal role of irritant contact dermatitis, as well as all the other factors contributing to occupational dermatitis, will lead to improvement in outcomes for patients.