Cognitive Bias Modification (CBM) has opened up new ways to treat addiction by retraining relatively automatic, maladaptive processes implied in the onset and maintenance of addiction disorders (Wiers et al., 2013). Many CBM interventions can, in principle, be administered online, thus showing potential of being a cheap addition to conventional treatments. The recent re-framing of pathological gambling (PG) as a behavioural addiction and its inclusion in the substance and addictive disorders diagnostic section of the new DSM-5 questions whether PG could also be explained by recent dual-process models of addiction and, consequently, whether CBM interventions can be potentially effective in the treatment of PG. Furthermore, the online delivering of CBM is believed to be of great value for PG treatment, since providing interventions via the Internet can increase the accessibility to help resources for gamblers by also circumventing many of the barriers associated to traditional in-person treatment (Ladoucer, 2005). In this talk we will go through the premises and the design of the first Randomised Clinical Trial exploring the effectiveness of two web-based CBM interventions targeting automatic selective attention and approach tendencies towards gambling-related cues in a sample of Dutch and Belgian problematic and pathological gamblers. Finally, preliminary results of the ongoing RCT are here presented for the first time.