1 Recent Developments in the Synthesis of Cyclic Guanidine Alkaloids, Matthew G. Donahue<br>2 Heterocyclic chemistry: a complete toolbox for nanostructured carbon materials, Stefano Cicchi<br>3 Three-Membered Ring Systems, David J. Lapinsky<br>4 Four-Membered Ring Systems, Benito Alcaide and Pedro Almendros<br>5.1 Five-Membered Ring Systems: Thiophenes and Se/Te Derivatives, Edward R. Biehl<br>5.2 Five-Membered Ring Systems: Pyrroles and Benzo Analogs, Justin M. Lopchuk<br>5.3 Five-Membered Ring Systems: Furans and Benzofurans, Xiao-Shui Peng, Renhua Fan and Jie Wu<br>5.4 Five Membered Ring Systems: With More than One N Atom, Larry Yet<br>5.5 Five-Membered Ring Systems: With N and S (Se) Atoms, Yong-Jin Wu<br>5.6 Five-Membered Ring Systems: With O & S (Se, Te) Atoms, R. Alan Aitken and Lynn Power<br>5.7 Five-Membered Ring Systems with O & N Atoms, Franca M. Cordero, Donatella Giomi and Luisa Lascialfari<br>6.1 Six-Membered Ring Systems: Pyridines and Benzo Derivatives, Tara L. S. Kishbaugh<br>6.2 Six-Membered Ring Systems: Diazines and Benzo Derivatives, Alison Rinderspacher<br>6.3 Triazines, Tetrazines and Fused Ring Polyaza Systems, Anton M. Prokhorov and Dmitry N. Kozhevnikov<br>6.4 Six-Membered Ring Systems: With O and/or S Atoms, Clementina M. M. Santos and Artur M. S. Silva<br>7 Seven-Membered Rings, John H. Ryan, Jason A. Smith, Christopher Hyland, Adam G. Meyer, Charlotte C. Williams, Alex Bissember and Jeremy Just<br>8 Eight-Membered and Larger Rings, George R. Newkome