The defining characteristic of sociological labour market research today is the prevalence of empirical evidence over theory. In order to fill this gap, this contribution collects and compares selected approaches from a variety of social-theoretical traditions (e.g. rational-choice, neo-marxism, economic and sociological institutionalisms, field-theories). As a result, the existing (fragments of) sociological labour market theories are grouped into four distinct streams of thinking with a focus on economic or social operators, on the one hand and agency or structure, on the other. In the light of current developments of social closure and protectionism of nationally embedded employment systems, the authors opt for a political sociology of labour markets based on sociological field theories.