This book is the result of student Leticia Mirielle Gonçalves de França Costa's Final Course Work in Social Work (PUCPR), supervised by Professor Dr Solange Fernandes, and is the fruit of joint reflections and shared concerns about the condition of animals in our society. Based on the understanding that the phenomenon of exploitation and domination of non-human animals does not happen in isolation, but is directly related to the major structures that shape society and generate inequalities and oppression, namely: patriarchy, racism, capitalism and speciesism, we sought in this work, through a bibliographical study, to analyse the human-animal relationship from a critical perspective, involving the ethical, environmental, political and economic issues present in this relationship. Finally, we set out to understand how the animal issue relates to the Ethical-Political Project of Social Work, bringing arguments in defence of including the debate around the animal cause in professional struggles for a free, fair and equal society.