Work it Out! is a guide for young adults who are switching from studying maths, science and economics in their first language to maths, science and economics in English. There are hundreds of thousands of such students around the world. They may be studying in high schools and colleges in their home countries or as new arrivals in English-speaking countries. They want to become engineers, scientists, accountants, teachers or business managers and they know that English is an important route to academic and professional success. Work it Out! doesn't teach maths: it teaches the language of maths. It introduces basic maths vocabulary and -through reading, speaking, listening and writing exercises- brings students (with an intermediate level of English) to fluency in expressing quantities, relative values and numerical relationships in English. Its student-centred approach means that Work it Out! also encourages students to work independently and to think critically. Many students have been taught maths through the learning of rules and then applying them. Work it Out! taps into students' deductive skills and they are trained to write their own word problems and to solve each others' word problems. Word problems in English are particularly challenging but most students realise they are unavoidable. They know that their future working lives as engineers, accountants, scientists or company managers will consist largely of discussing and solving these kinds of problems.