UV radiation (UVR) is invisible to the human eye, so is also, at least according to the official statistics in most countries, the prevalence of skin cancer caused by UVR at the workplace. For that reason, skin cancer by UVR (mainly actinic keratosis, squamous cell carcinoma and basal cell carcinoma) is a mayor challenge, considering that it is the most frequent and fastest growing occupational malignancy. According to EUOSHA more than 14.5 million workers across the EU are regularly working outdoors by ≥75% of their daily working hours. Thus, outdoor workers are in need of targeted protection against UVR, representing the group I definition for a complete carcinogen to humans according to IARC. Specific prevention measures, including workers education, early diagnosis and medical screening are crucial to minimise the risks and to reduce morbidity. Few European countries recognise occupational skin cancer by UVR as an occupational disease. Yet, even in those few countries, workers with skin cancers related to chronic, work-related solar UVR exposure are not granted legal recognition because under-reporting is tremendous. For instance, in Denmark, in the decennium after introducing of recognition in 2000, only 35 cases had been legally acknowledged as occupational. Recent German figures may provide an estimate of the disease burden. Within the first 24 months from its recognition (2015), more than 8000 cases of occupational ‘cutaneous squamous cell carcinoma or multiple actinic keratoses’ are notified each year, making it the most frequent occupational disease e.g. in agriculture and construction, as well as the most frequent occupational cancer of all branches. The magnitude of affected workers and recent dosimetric UVR measurements showing high annual exposures (>600 SED) are currently stimulating regulatory efforts for improved workplace prevention. The recognition of UVR induced skin cancer as an occupational disease, has proven to be pivotal to this approach.