Option for the Poor & Vulnerable

Along with

•The Right to Life & the Dignity of the Human Person
•Call to Family, Community & Participation
•Rights & Responsibilities
•Dignity of Work & the Rights of Workers
•Solidarity
•Caring for God's Creation

the United States Conference of Catholic Bishops explains that Option for the Poor & Vulnerable is one of the seven key themes of Catholic Social Teaching:

"While the common good embraces all, those who are in greatest need deserve preferential concern. A moral test for society is how we treat the weakest among us— the unborn, those dealing with disabilities or terminal illness, the poor and marginalized."

As per Chapter 4 of the Compendium of the Social Doctrine of the Church,

“The permanent principles of the Church's social doctrine constitute the very heart of Catholic social teaching. These are the principles of:

the dignity of the human person, ...which is the foundation of all the other principles & content of the Church's social doctrine;
the common good;
subsidiarity; and
solidarity....

"The principle of the universal destination of goods requires that the poor, the marginalized and in all cases those whose living conditions interfere with their proper growth should be the focus of particular concern. To this end, the preferential option for the poor should be reaffirmed in all its force”