This work represents a comprehensive, systematic study of conjugated oligomers for electronics applications. Summary of contents: 1. Hydrocarbons 2. Oligothiophenes 3. Tetrathiafulvalenes 4. Nitrogen-containing Oligomers 5. Cofacial Porphyrins and Phthalocyanines 6. Oligomeric Metal Complexes 7. Crystal Structures 8. Packing Calculations 9. Vibrational Spectra 10. Electronic Excitation 11. Experimental/Electronic Excitation: Quantum Chemical Interpretation 12. Non-linear Optical Properties 13. Electrochemical Properties 14. Electrical Properties 15. Optical Applications 16. Electrical Applications 17. The Future