Macrocyclic ligands have been prepared by various one-step cyclooligomerization processes. This short review covers one-step cyclization reactions involving the formation of four to twenty or more new covalent bonds. The new macrocycles reviewed include cyclophanes, biscrown ethers, cryptands, macrolides, cage compounds, calixarenes, homocalixarenes, cucubiturils, and supercryptands all prepared by one-step syntheses.