The high level of satisfaction of users of a health service is largely due to the fact that they receive excellent care from healthcare professionals. Compassionate care is an essential component of excellent care. But what do nurses understand compassion to be? To analyse the concept of compassion from the perspective of nurses in the Andalusian Public Health System, Spain. This is a qualitative study following the grounded theory model. Four focus groups and 25 in-depth interviews were conducted. A total of 68 nursing professionals working in the Andalusian Public Health System (Spain) participated. Theoretical sampling was used, with participants being recruited using the snowball technique. This research was approved by the Research Ethics Committee of the Centro-Almería Health District (CEICA 27/9/17). From the analysis of the data, four themes emerged that helped to understand the concept of compassion according to nurses: 'Negative perception of the term compassion', 'Compassion and empathy as synonyms', 'Beyond empathy', and 'Effects of having a compassionate attitude'. Nurses perceive the concept of compassion differently to each other and even contradictorily. This concept is imbued with cultural elements, which adds confusion to understanding it, and is even perceived as something negative similar to pity. Nurses confuse the concepts of empathy and compassion as if they were synonymous. Before considering training in compassion for healthcare professionals, it is essential to clarify the concept of compassion through educational interventions.