Guidelines for teachers of English to speakers of other languages (ESOL) who wish to undertake an ESOL materials development project are presented. Three areas that affect all such projects are discussed: (1) writing for a local or a wider audience, (2) writing as a team effort, and (3) writing as a decision-making process. In creating for a local audience, the writers are familiar with the needs of the learners, their ages, level of proficiency, degree of motivation, and cultural learning styles. At the same time, there is complete information about the instructional setting: class number, number of hours of instruction, and languages used by learners in and outside of the classroom. Parameters of the project should be defined in terms of emphasis on language skills, structural elements and processes, functions, and content. A team needs an organizer, an idea person, an experimenter, and an evaluator. In team writing, one person is totally responsible for conceptualization and design and for task assignment. The decision-making characteristics of materials writing is most apparent during the early stages of a project. Among the basic issues that should be settled early are: (1) Is the project needed? (2) Is the project focused on real needs of the intended audience? (3) Whose voice will speak from the pages (teacher or author)? (4) What will the student's responsibility be? Language content concerns are: selection and suitability of content, selection of context, grading, and the point of view expressed in terms of age, sex, social class, and nationality. The format, sequencing, practice modes, and evaluation of the materials also are important. (SW)