PROJECT SUMMARY This supplement request seeks to add task-based fMRI data to the data pooing efforts of the ENIGMA-Addiction group). ENIGMA-Addiction performs secondary mega- and meta-analyses of addiction-relevant neuroimaging- genetic datasets. The data pooling addresses the substantial concerns that exist within the neuroimaging field related to small samples leading to very poorly powered studies. Currently, ENIGMA-Addiction includes 152 unique studies, contributed by 86 Principal Investigators at 57 different institutions in 17 countries, totaling approximately 20,000 participants and, additionally, works with publicly available datasets (e.g., ABCD, HCP, UKBiobank). Thus far, we have focused on structural data (high resolution anatomical and diffusion weighted scans) and resting-state functional connectivity data. However, this is an ideal time to expand into task-based functional MRI, specifically, brain activation (and functional connectivity) during the presentation of substance- related cues called fMRI drug cue-reactivity (FDCR). Our recent systematic review of FDCR studies has identified 357 studies published from 1998 to 2020 (Ekhtiari 2022). Although there are heterogeneities in the details of the conducted studies, 252 of the 357 studies used pictorial cues and 217 of them used a blocked design. Moreover, we have tackled the methodological reporting issues in our recent consensus study (Ekhtiari et al. 2022) and there are now well-established procedures developed by a dedicated ENIGMA working group for the harmonized analyses of multi-site task-based fMRI data. We will collect minimally pre-processed data from the interested labs across the world with our existing ENIGMA-Addiction procedures. Primary analysis will consist of a mega-analysis of output from co-registered and pre-processed functional BOLD scans for individual participants using ENIGMA HALFPipe, to obtain and compare whole-brain drug>neutral contrast maps for participants with and without SUD and store them in BIDS format.