The present study aimed at enhancing third-year secondary school students' reading comprehension and expository writing skills through expanding their knowledge of textual cohesion and coherence. It adopted the qusai-experimental pre-post test one group design. Participants of the study comprised 39 students at Manfalut Secondary School for Girls, Assiut Governorate. Through a proposed program, they received training on identifying and using various textual features, with particular focus on text structure and textual cohesion and coherence. Instrumentsof the study included: a reading comprehension skills checklist, an expository writing skills checklist, a reading and writing skills pre-post test, a software tool for corpus analysis, a student satisfaction questionnaire and a reflection log. Study results yielded statistically significant differences at 0.01 level between the mean scores of the pre and post tests. The results indicated that the program had a large positive effect on the participants' overall skills in reading comprehension and expository writing. In addition, a written discourse analysis of participants' essays in the pre-test revealed that many third-year secondary school students lacked sufficient knowledge of textual cohesion and coherence and faced various difficulties in using grammatical and lexical cohesive devices. The satisfaction questionnaire indicated that the majority of the students benefited from the program, though some believed that it was difficult. It was concluded that teaching textual cohesion and coherence enhances students' reading comprehension and expository writing skills. Pedagogical implications suggest embedding the teaching of textual cohesion and coherence into EFL course books and tutorial materials, especially in the secondary stage.