Avian phylogeny in general is well investigated and some clades have received particular attention, e.g. Galliformes, Coraciiformes, Trogoniformes and Passeriformes. However, a number of clades have received little or very little attention. Therefore, I included this chapter hoping to direct future research efforts towards the following clades:

• Accipitriformes: Accipitridae
• Anseriformes: Anatidae
  
• Ciconiiformes: Ciconiidae
• Cuculiformes: Cuculidae
• Gruiformes: Gruidae
  
• Otidiformes: Otididae
• Pelecaniformes: Threskiornithidae & Ardeidae
• Podicipediformes: Podicipedidae
• Strisores: Apodidae