Wildfire detection systems planning is an essential component of national and regional wildfire management policies. The common resources usually used in wildfire detection are lookout towers, terrestrial mobile brigades, aerial reconnaissance and the general public. The objectives of this paper are (i) to analyse the relative importance of the different detection systems in Portugal and Spain, according to their spatial and temporal patterns, (ii) to assess the territorial variables related to the performance of fire detection systems in the Iberian Peninsula, and (iii) to develop an explanatory model aiming to inform fire detection policies. Pursuing this aim, a common wildfire and territorial database for the whole Iberian Peninsula was developed, thus enabling common cartographic and statistical analyses. Results show the importance of land cover variables and population density on the proportion of fire detections made by the different systems in both countries. Despite certain national specificities, many common features were found, allowing the identification of general patterns of fire detection distribution and performance for the Iberian Peninsula. Models developed at the regional and sub-regional levels indicate that high population density and high proportion of forestlands are associated with higher proportion of detection by population, whereas higher proportion of shrublands corresponds to higher proportions of detections by other systems, particularly lookout towers. The conclusions obtained and the approaches applied could be used with similar objectives in other countries and regions to inform policy decisions regarding the allocation of resources for wildfire detection.