Older adults (65+) are often considered to be technologically less savvy than the average population, particularly with respect to using online applications [4]. This can have negative consequences for their financial, health, and well being, by hindering their access to resources such as online banking, relevant health information, and connections with family members and friends. The 2011 Census [7] indicate that 66% of such adults are daily Internet users; as such, it is important to also protect older adults' online safety and privacy – especially since seniors are a significant target of Internet scams or email phishing attacks. Solutions have been proposed to address this significant problem; however, these are not widely reaching – just in one year alone, older Canadian adults have lost an estimated $10 million to Internet scams [2]. Moreover, there is very little understanding of why seniors are disproportionately falling victim to online threats, despite the availability of various technologies that block such threats (e.g. browser add-ons). For this, we have begun studying the technological and non-technological barriers to the adoption of digital security technologies by older Internet users, and exploring design changes that increase their adoption. This paper presents a preliminary investigation of a participatory design approach to developing adoptable and usable online security interfaces for older adults.