The value of taking advantage of the participants' interactions when analyzing focus group data is often stressed. However, there is a lack of detailed descriptions of how focus group data can be merged with interview data, and considered throughout a thematic analysis process. This article describes a systematic way to include focus group interactions in data analysis, using a coding scheme. The aim was threefold: to develop a coding scheme for focus group interactions; to test and describe a process for interaction analysis, merged into the thematic data analysis process, and to test the coding scheme on another dataset. Based on focus group literature a comprehensive coding scheme for analyzing focus group interactions, was developed, including symbols for these interactions. Data from five focus group interviews involving adolescents were subsequently coded using this scheme. Further analysis of the identified interactions was conducted simultaneously with thematic data analysis, using Systematic Text Condensation (STC) as an illustrative method. The coding scheme was then tested on data from a different focus group involving adolescents in another setting. A comparison between the two coders was made, leading to a slight modification of the coding scheme. The resulting coding scheme is a practical tool adding to the previous knowledge on focus group interaction analysis. More specifically, the scheme facilitates focus group interactions to be visible and accounted for thought the thematic analysis process.