HartiSWIM is a family-led sustainable luxury swimwear brand founded by Dr Tessa Hartmann CBE, whose collections feature hand-painted pop art prints by artist Sascha "Harti" Hartmann translated onto premium recycled fabrics made from post-consumer plastic bottles. The range spans swimwear, resort wear, bespoke Harti Atelier made-to-order pieces, and homeware, all made in Italy and designed to reject fast fashion. HartiSWIM also extends into ocean conservation activism and original music under the H Collective banner.