Families living with mental illness experience an added burden and may experience such psychological distress that they require therapeutic intervention. The Internet is used as a daily tool by a growing share of the population worldwide, including for health related matters. Its potential as a health care tool, including advantages and drawbacks, should be explored. The overall aim of the present thesis was to explore the relatives’ experiences of living close to a person with depression and the Internet’s potential to address their needs. Explorative qualitative research has been used to map the e-health field in relation to depression, to explore what the Internet offers the families living with depression, as well as the relatives’ experiences of living with a person with depression. An iterative design process was used in the development of a digitally based tool aimed at supporting the relatives in their daily life with depression. Users’ experiences of the tool were explored using qualitative explorative research. A vast array of different organizations and initiatives are represented within the e-health field. However, initiatives that are targeted and tailor-made for families living with depression are scarce. Research in the e-health field with focus on depression illuminates health seekers’ and online community users’ profiles, effects of online cognitive behavioral therapy (CBT), and a number of strengths (i.e. accessibility) and weaknesses (i.e. reliability) related to the Internet as a health care tool. Living close to a person with depression can strongly affect the private, social and professional areas of the relatives’ daily life. A growing feeling of not living one’s own life may arise, due to the difficulties of balancing relationships, a process of adaptation and re-evaluation of life circumstances, and a struggle to act as advocate and voice for the person with depression within the health care system and society. Relatives often come in contact with health professionals on 12 behalf of their ill kin and need information and support; needs that are rarely addressed by the health care system. A digitally based tool aimed at supporting the relatives in their daily life with depression was developed using an iterative design process. The tool’s development was carried out in close cooperation with users with the help of focus groups and prototypes. Motivations and obstacles to using online self-help tools were illuminated. Privacy stood out as an important factor when developing online tools. The study resulted in a website, www.sommarregn.se, entailing an online diary (private and encrypted), including scales, and a forum (members only access), including an e-mail function. Users’ experiences of the website over a 10 weeks test period were illuminated. The diary and forum appeared to fill a number of valuable functions, although a further development of the tool may enhance its usability, which was good. The tool promoted communication with the self and others. The Internet as a technology offered a number of advantages, such as convenience of use and perceived anonymity, and disadvantages, such as qualitative issues. The relatives’ needs ought to be addressed in order to support them in a daily life with depression. Empowered relatives are in a better position to help their ill kin and support may prevent ill health in the relatives themselves, and subsequently additional costs to society. Health care professionals meet patients that are also online health seekers. Professionals must be aware of the advantages and drawbacks of e-health when meeting patients. In an economically pressured society, alternative support options have to be explored in order to address the needs of target groups at risk.