Cities have witnessed the disappearance of natural habitats, putting biodiversity at risk and leaving citizens with a diminished connection to nature. Establishing a strong human-nature connection is crucial for sustainable transformations in society, influencing sustainable norms, values, and policy decisions. Urban Reef, a company specializing in 3D-printed ceramic Reefs, offers a solution to improve urban biodiversity by hosting various living species. These Reefs are considered “living artefacts” as they evolve over time with the colonization of natural species. However, little research has been conducted on the social dimension of such living artefacts and how they can positively impact human users and their connection to nature. To address this knowledge gap, this research aimed to explore how Living Artefacts, like Urban Reef’s Reefs, can help urban citizens feel more connected to nature. The project employed a combination of Research through Design and Co-creative Design approaches to answer this question. The research commenced with a user study conducted during a family science day, utilizing interactive posters, observations, and the creation of clay seed combs. The results, along with a literature review, revealed a limited connection to and awareness of nature within urban environments. However, the study also demonstrated the potential of engaging with Reefs to enhance nature connectedness. In the subsequent phase, a citizen science study involving five participants caring for and monitoring a Reef showcased improvements in human-nature connectedness. Participants experienced a shift in their perception of nature and developed meaningful bonds with the Reef. Drawing upon the citizen science findings and an extensive literature review, a comprehensive collection of design guideline cards for living artefact designers was created. The card set encompasses seven pathways to increase nature connectedness through living artefacts: Living Aesthetics, Interactions, Affective Response, Habitabilities, Care & Compassion, Views of Nature, and Ecological Knowledge. These cards serve as a valuable resource for designers, providing diverse approaches to adapt ideas, designs, and prototypes to create living artefacts that foster a stronger connection between urban citizens and the natural environment. Moreover, the cards feature concrete examples of Living Artefacts, offering tangible illustrations to support and inspire designers in their creative process. Additionally, three concept designs were developed by applying the design cards to Urban Reef’s existing Reefs, serving as illustrative examples of potential outcomes achievable through the utilization of the design guidelines. The thesis project concluded with a user evaluation of the design concepts, followed by recommendations for the future development of Urban Reef. These recommendations aim to guide the market introduction of Reefs in the coming years. The thesis project also provides additional recommendations for further refining the design guidelines. In summary, this research project highlights the importance of fostering a human-nature connection in urban environments. Through the exploration of Living Artefacts, such as Urban Reef’s Reefs, and the development of design guideline cards, this project offers insights and tools for designers to create living artefacts that enhance nature connectedness among urban citizens.