Objectives: Kaizen, or continuous improvement, lies at the core of lean. Kaizen is implemented through practices that enable employees to propose ideas for improvement and solve problems. The aim of this study is to describe the types of issues and improvement suggestions that hospital employees feel empowered to address through kaizen practices in order to understand when and how kaizen is used in healthcare. Methods: We analysed 186 structured kaizen documents containing improvement suggestions that were produced by 165 employees at a Swedish hospital. Directed content analysis was used to categorise the suggestions into following categories: type of situation (proactive or reactive) triggering an action; type of process addressed (technical/administrative, support and clinical); complexity level (simple or complex); and type of outcomes aimed for (operational or sociotechnical). Compliance to the kaizen template was calculated. Results: 72% of the improvement suggestions were reactions to a perceived problem. Support, technical and administrative, and primary clinical processes were involved in 47%, 38% and 16% of the suggestions, respectively. The majority of the kaizen documents addressed simple situations and focused on operational outcomes. The degree of compliance to the kaizen template was high for several items concerning the identification of problems and the proposed solutions, and low for items related to the test and implementation of solutions. Conclusions: There is a need to combine kaizen practices with improvement and innovation practices that help staff and managers to address complex issues, such as the improvement of clinical care processes. The limited focus on sociotechnical aspects and the partial compliance to kaizen templates may indicate a limited understanding of the entire kaizen process and of how it relates to the overall organisational goals. This in turn can hamper the sustainability of kaizen practices and results.