Accessibility is an important element in the life of those who have certain limitations, such as the physically disabled and visually impaired people. However, one of the greatest challenges for this group is to find paths and areas adapted to their limitations while performing their daily activities, since not all environments they explore have these characteristics. Volunteered Geographic Information (VGI) and the crowdsourcing technique appear to be quite useful to develop solutions to overcome these challenges, since these techniques are naturally cheap as they rely on human sensors as the main agent of information delivery. In this chapter, we discuss how these techniques can help mitigate accessibility problems and present some existing research and applications in the field.