Despite increasing numbers of publications showing that many animals possess the neural substrates involved in emotions and consciousness and exhibit agency in their behavior, many animals are still restrained and forced to take part in applied or fundamental research. However, these restraints and procedures, because they stress animals and limit the expression of adaptive behavior, may result in compromised findings. Researchers should alter their research paradigms to understand the mechanisms and functions of the brain and behavior so that the paradigms incorporate animals' agency. This article discusses how animal agency cannot only be the key to more wide-ranging and improved research in existing domains but can also lead to new research questions about behavior and brain evolution. (PsycInfo Database Record (c) 2023 APA, all rights reserved).