## 2 Materials and Methods  
Being a participative land administration approach, the community is always involved in each step of the FFP application in Colombia, as can be seen in Figure 1. The point of departure in the application of FFP in Colombia is a socialisation process with all the stakeholders present, followed by a social cartography session. Here, the land users first indicate their parcel boundaries on a large, printed map on which the official parcel information on top of a satellite image is visible. Most parcel boundaries are defined by natural boundaries, such as rivers or streams, but depending on the available imagery of the specific region, these boundaries cannot always be identified in the satellite image. In case there is not much vegetation in the area and high-resolution imagery is available, land boundaries can be identified more precisely during the social cartography session. When more precise boundary definitions are necessary, the community is invited to measure the boundaries in the field. During the field measurements, the vertices of the parcel boundaries are indicated by the land user and the coordinates of each vertex are recorded with a Global Network Satellite Systems (GNSS) antenna. These points are recorded with the mobile application Esri Collector on a standard smartphone (Android or iOS). This application is connected by Bluetooth to the GNSS antenna to capture the coordinates (latitude and longitude), as well as the horizontal and vertical accuracy and the number of found satellites, among other things. The antenna is always handled by the land user themselves--in this case, the Indigenous leader or settler farmer--with the objective that they can measure the boundaries of their property according to their local knowledge and perceptions. The Indigenous leader decides what information is collected and communicates this with his community. This generates confidence in the processes since the perception of the Indigenous peoples is deciding. The Esri Collector app is operated by a grassroots surveyor, a local youngster who has received a short FFP data collection training session. The grassroots surveyor is supervised by a professional surveyor for quality control, technical assistance, and coordination. Both spatial and legal information are gathered in one run per land user in the Esri Collector app, which assures integrated data collection. The measurements of the parcel are visualised in the app as polygons, which makes it possible to directly show the shape and size of the property to the land user. The legal collected data are names, ID number, and date of birth of the right holder(s) with a photograph of the person(s) and their ID card(s); a picture of the parcel; a description of the right holder(s) relationship with the parcel; and photographs of the documents that provide proof of some kind of land right or long-term land use. After data collection, all data are uploaded to a PostgreSQL database. To protect Indigenous Data Sovereignty, the CARE principles (Collective benefit, Authority to control, Responsibility and Ethics) are taken into account [34]. The Indigenous peoples decide what is captured in the field. This includes the boundaries of their reserve, based on  
Figure 1: The fit-for-purpose (FFP) methodology steps as applied in the Colombian Land in Peace Project. Elaborated by the authors. Source: Land in Peace Project, Kadaster. local and historical knowledge, but also traditional and sacred places for the Indigenous peoples. Collected data are afterwards checked with the Indigenous leaders, maps of all measured places are shown, and they have the opportunity to modify and add information that is important to their community. Colombian governmental institutions can only use data that are officially approved by the Indigenous peoples. The technology that is used in the FFP application in Colombia was developed to meet the purpose, to develop a participative approach of capturing relationships between land and its users, for the Colombian situation.