Signaling by diffusible morphogens, such as Hedgehog, Wingless, TGF-, and various growth factors, is essential during embryogenesis. The establishment of concentration gradients of these morphogens is vital for developmental patterning, ensuring that distinct differentiated cell types appear in the right place and at the right time in forming tissues. Written and edited by experts in the field, this volume explores how morphogen gradients are generated and interpreted during development. The contributors examine the regulation of morphogen synthesis, trafficking, and diffusion, as well as the...