The objectives of this research are to find the proper measures to improve efficiency of Thai-Lao cross border transportation (R9 route) for Thai shippers and study their performance after implementing the developed measures. This research implements both quantitative and qualitative research, where the population of this research consists of shipper’s groups which transport products via the Thai Lao border located along R9 route. The research tools are questionnaire and structured interview form passed variability and reliability tests. Then the questionnaires are distributed to 3 large size firms (sample size of 316 people) and an in-depth interview with 18 people. This research analyzes gathered data using descriptive analysis, construct validity, structural equation modeling (SEM), path analysis, and content analysis for qualitative data. The analysis results reveal important findings according to each research objective as follows. For the first objective, to improve cross-border transportation, the case study firms should concentrate on three measures as: 1) transportation safety in terms of sound safety control and monitor, increasing rest areas and truck stops including those on pavement or roadside, safety monitoring during transportation, and weather conditions checking; 2) documentation procedure in terms of reducing the procedure steps, IT implementation, and procedure improvement both inbound and outbound; and 3) vehicles management in terms of appropriate resources allocation, facilities availability, and appropriate resources selection. For the second objective, the study of the case study firms’ performance after implementing the developed measures, it reveals benefits in several aspects of 1) cheaper (they can deliver items with lower costs, lower expenses, or lower price than before implementation as well as other competitors); 2) faster (better customers responsiveness, faster delivery and operating than other competitors, and lead time reduction), and 3) better (in operations with less bottlenecks, mistakes, and disruptions manifested in delivery; higher competitiveness and better service quality). To summarize, the implementation of the developed model can help the shippers to increase their capability as well as their competitiveness.