This paper presents an analysis of the major generic structures of empirical research articles (RAs), with a particular focus on disciplinary variation and the relationship between the adjacent sections in the introductory and concluding parts. The findings were derived from a close "manual" analysis of 433 recent empirical RAs from high-impact English-language journals in 39 disciplines in the fields of engineering, applied sciences, social sciences and the humanities. This analysis reveals that while many empirical RAs follow the "standard" Introduction-Method-Results-Discussion (IMRD) pattern, this structure is not the default option for organizing such studies. The findings indicate that the most frequently used structural pattern is Introduction-Literature Review-Method-Results and Discussion-Conclusion (ILM[RD]C). The other prominent patterns found in the corpus are IM[RD]C, IMRDC, ILMRDC and ILMRD. The paper identifies and highlights the importance of the sections that are not fully accounted for in the conventional IMRD framework, namely the Literature Review (L), the merged (as opposed to separated) Results and Discussion [RD], and the Conclusion (C). The paper concludes by discussing the implications of the study for academic writing research as well as the design of RA writing courses and materials for research students and early-career academics. (Contains 2 figures.)