[1] Gustav started his career as a volunteer for the Guildhall Museum at the site of Custom House in the City of London.
[7] In 2015 he helped create the Coastal and Intertidal Zone Archaeological Network (CITiZAN) which he currently holds the position of Project Leader, and the founder and co-ordinator for UCL 'Evolutionary Determinants of Health' programme.
[3][8][9] Gustav has also set up the Museum of London's Centre for Human Bioarchaeology with a grant from the Wellcome Trust.
[11] He has also appeared as a contributor to Digging for Britain - The Tudors and TV documentaries The Bridges That Built London and Fire, Plague, War and Treason.
Through his project leadership at CITiZAN, in 2016 he assisted Tern TV in setting up the archaeology program Britain at Low Tide.