There are good things to say about the field of second language cognitive task complexity research. It shows great vitality and has produced a wide range of interesting findings. Yet there are, in this young field, signs of fragmentation (and even disorganisation). There is an urgent need to take stock, to synthesise, and to look at the future in a more systematic way. This volume is a wonderful contribution to addressing all these concerns, representing a landmark publication that has the potential to shape task research in coming years. It offers concise and perceptive analyses of tasks and task characteristics, clarifying many of the disagreements and inconsistencies that abound. It also provides authoritative coverage of measurement problems and solutions with second language task-based performance. Above all, the scale, the scope of coverage is astonishing—it does justice to, and synthesises a huge literature, an excellent preparation for the meta-analysis which follows. The meta-analysis results themselves make a massive contribution. Not only do they provide authoritative coverage (and clear findings) of variables such as planning, repetition, familiarity, and others, the analysis also reveals under-researched areas, such as proficiency effects, and how addressing such gaps is vital for the future. It also functions as a vital handbook for researchers in designing future studies—giving them a framework which will help to combat isolated, detached research. Finally, the range of findings and the generalisations which emerge, such as the role of planning, will have a major impact on pedagogy.

There are good things to say about the field of second language cognitive task complexity research. It shows great vitality and has produced a wide range of interesting findings. Yet there are, in this young field, signs of fragmentation (and even disorganisation). There is an urgent need to take stock, to synthesise, and to look at the future in a more systematic way. This volume is a wonderful contribution to addressing all these concerns, representing a landmark publication that has the potential to shape task research in coming years. It offers concise and perceptive analyses of tasks and task characteristics, clarifying many of the disagreements and inconsistencies that abound. It also provides authoritative coverage of measurement problems and solutions with second language task-based performance. Above all, the scale, the scope of coverage is astonishing—it does justice to, and synthesises a huge literature, an excellent preparation for the meta-analysis which follows. The meta-analysis results themselves make a massive contribution. Not only do they provide authoritative coverage (and clear findings) of variables such as planning, repetition, familiarity, and others, the analysis also reveals under-researched areas, such as proficiency effects, and how addressing such gaps is vital for the future. It also functions as a vital handbook for researchers in designing future studies—giving them a framework which will help to combat isolated, detached research. Finally, the range of findings and the generalisations which emerge, such as the role of planning, will have a major impact on pedagogy.

There are good things to say about the field of second language cognitive task complexity research. It shows great vitality and has produced a wide range of interesting findings. Yet there are, in this young field, signs of fragmentation (and even disorganisation). There is an urgent need to take stock, to synthesise, and to look at the future in a more systematic way. This volume is a wonderful contribution to addressing all these concerns, representing a landmark publication that has the potential to shape task research in coming years. It offers concise and perceptive analyses of tasks and task characteristics, clarifying many of the disagreements and inconsistencies that abound. It also provides authoritative coverage of measurement problems and solutions with second language task-based performance. Above all, the scale, the scope of coverage is astonishing—it does justice to, and synthesises a huge literature, an excellent preparation for the meta-analysis which follows. The meta-analysis results themselves make a massive contribution. Not only do they provide authoritative coverage (and clear findings) of variables such as planning, repetition, familiarity, and others, the analysis also reveals under-researched areas, such as proficiency effects, and how addressing such gaps is vital for the future. It also functions as a vital handbook for researchers in designing future studies—giving them a framework which will help to combat isolated, detached research. Finally, the range of findings and the generalisations which emerge, such as the role of planning, will have a major impact on pedagogy.