This report describes the development of efficient second language (L2) writing assessment tasks designed specifically for low proficiency learners of English to be included in the TOEFL Essentials test. Based on the can-do descriptors of the Common European Framework of Reference for Languages for the A1 through B1 levels of proficiency, four task types were identified to be prototypical candidate writing tasks for the target test-taker population (i.e., adolescent and adult low-proficiency English learners). Those four task types included: (a) Describe a Photo, (b) Write a Review, (c) Chat With a Friend, and (d) Write an E-mail. These task types were also considered efficient in the framework of the test in that they had the potential to be accessible to low-proficiency learners and to elicit sufficient spontaneous writing for assessment purposes within a short period of time. In the current study, eight assessment tasks, two for each task type, were developed and piloted with 169 A1–B1 learners of English from Japan and Colombia. The findings revealed that the Describe a Photo and Write an E-mail tasks performed the best in eliciting substantial language use and emphasizing distinct performance attributes, both characteristics needed for efficiently measuring test takers’ writing proficiency as well as discriminating among proficiency levels at the lower end of the spectrum. The report concludes by highlighting some observations on L2 writing assessment task design for low-proficiency learners of English.