OBJECTIVES: To develop a Markov model for an economic evaluation of a hypothetical intervention in chronic obstructive pulmonary disease (COPD), to implement it in TreeAge and ARENA in order to ensure its technical validity and to compare ease of implementation. METHODS: We used a 7-state Markov model (disease stages I to IV according to GOLD classification, post-surgery, post-transplantation and death) with a time frame of 60 years to assess incremental costs (€) and effects (life-years gained, LYG). Applying identical assumptions regarding transitions and costs, we ran Monte Carlo simulations with 10,000 patients for 100 replications in both packages. Additionally, we calculated expected values for the TreeAge model. RESULTS: In TreeAge, the simulation resulted in higher incremental costs and effects compared to ARENA (p<0.0001). Standard errors in both packages were equal for effects, but slightly higher for costs in ARENA. For the TreeAge model, averaged simulated values of both costs and effects were close to the expected values, indicating adequate sample size. Run-time was slightly shorter in ARENA. Yet determining cost-effectiveness values was more convenient using TreeAge. CONCLUSION: Building a standard Markov model for cost-effectiveness calculations appears more comfortable in TreeAge. Useful tools for calculating and plotting the results of an economic evaluation are available and can easily be applied. In ARENA, users must implement these features themselves, yet the user is more flexible when classical Markov assumptions no longer hold.