The studies by Santiago Ram6n y Cajal on astrocytes, and the extense work developed by Pio del Rio Hortega dealing with microglia and oligodendrocytes are with no doubt two important milestones of neurobiology, and specially cf glial research. Since these classical studies, the curiosity for understanding glial cells has continuously grown. During the last two decades, the development of new meth- ods of study, including cell culture techniques and the use of histochemical and immunocytochemical markers, has allowed a remarkable advance in this field. This increasing interest is reflected by the creation of local and international glial networks, the publication of the journal Glia, the celebration of periodic interna- tional meetings and the publication of extensive books focused on glial cells. In February 1997, with the establishment of the Spanish Glial Network, arose the early idea of publishing a compendium of selected work by Spanish glial research teams, which has fmally materialised in Understanding Glial Cel/s, a book whose objective is to present topics of current interest in glial cell biology.

The studies by Santiago Ram6n y Cajal on astrocytes, and the extense work developed by Pio del Rio Hortega dealing with microglia and oligodendrocytes are with no doubt two important milestones of neurobiology, and specially cf glial research. Since these classical studies, the curiosity for understanding glial cells has continuously grown. During the last two decades, the development of new meth- ods of study, including cell culture techniques and the use of histochemical and immunocytochemical markers, has allowed a remarkable advance in this field. This increasing interest is reflected by the creation of local and international glial networks, the publication of the journal Glia, the celebration of periodic interna- tional meetings and the publication of extensive books focused on glial cells. In February 1997, with the establishment of the Spanish Glial Network, arose the early idea of publishing a compendium of selected work by Spanish glial research teams, which has fmally materialised in Understanding Glial Cel/s, a book whose objective is to present topics of current interest in glial cell biology.

Although knowledge of the development and differentiation of glial cells has significantly increased in recent years, there are still many questions unanswered. The first section of the book is devoted to this very active topic and includes contributions on Schwann cells, oligodendrocytes, astroglia and microglia.

The second section of the book covers cellular interactions, the role they play on myelination and remyelination, how these interactions take place and the molecules involved.

The third section of this volume focuses on the interactions of neurons with glial cells and their role in brain function. Neuron-glia cross talk appears to be fundamental for synaptic transmission and several chapters in this section address this topic.

The topic of how glial cells react to brain injury and how they participate in neuroprotection and brain repair is covered in section four of this book. As our knowledge about the molecules involved in the regenerative properties of glia increases, new avenues are open for the use of genetically modified glia with therapeutic purposes.

The final section of the book is devoted to therapeutic approaches to tumours, viral and prion infections. Gene therapy is a promising approach for the treatment of gliomas, one of the most devastating forms of cancer. A chapter on prion diseases and microglia addresses a question of tremendous actuality, since prion diseases in cows is at this moment the major veterinary problem in Europe and has created a considerable social alarm.