This study aimed at investigating the characteristics of effective English teachers and students as perceived by 35 teachers and 613 students, as well as according to the surveys regarding the English-teaching problems in Thailand. The instruments included two questionnaires on the characteristics of effective teachers and students as perceived by teachers and students, based on five categories: rapport, delivery, fairness, knowledge and credibility, organization and preparation. The questionnaire responses were analyzed both quantitatively and qualitatively. The quantitative data revealed that for the teachers the most important attribute was organization and preparation attributes such as teaching preparation and the use of effective teaching methodology. The qualitative data revealed that the rapport items were important, especially that the teacher should be patient, not insult the students, and give clear advice. However, the students gave more weight to such rapport items as, for example, the teacher having a positive attitude toward to the students and being helpful, generous and caring about them. The qualitative data also revealed that well-prepared lessons and providing fun activities were mostly required for effective teachers. English teaching problems involve four aspects: teachers, learners, English learning content, and other factors. Discussion and the recommendations of the study are included.