In semantic fluency tasks, participants employ semantic search strategies (clustering and switching) to facilitate word retrieval. Clustering involves producing sequences of related words, while switching refers to shifting between different semantic categories. Analyzing these strategies provides insights into the structure of the mental lexicon in both native and foreign language. This study explored these strategies in a semantic fluency task with the prompt 'My country'. Fifty-three Greek learners of Spanish completed the task in both their native language (Greek) and foreign language (Spanish). Clustering was analyzed by the number of clusters, the mean cluster size and the type of cluster, based on the type of association among its members. Switching was measured by the number of transitions. Results revealed that participants produced more and longer clusters in their L1 than in SFL responses, reflecting a more developed and interconnected mental lexicon in the L1. Additionally, they made more switches in L1, likely due to greater cognitive control and flexibility in their native language, which facilitates the cognitively demanding process of switching. Cluster types were consistent across both languages, suggesting that the internal structure of the prompt and cultural background significantly influence lexical organization regardless of language proficiency. [For the complete volume, "Lexicon Exploration in English and Spanish Learners. Educational Linguistics. Volume 67," see ED676344.]