Abstract 1. Basic Properties of the Left Peripheral Constructions 1.1. Asymmetries in the Main Clause 1.2. Asymmetries in the Embedded Clause 2. Analysis with the Notion of Topological Fields 3. Extraction from an Embedded Clause 4. Other alternatives 4.1. Brief Comparison with Configurational Approaches 4.2. Lexical and Constructional Constraints 5. Conclusion References