Since biomass and bioenergy are global issues, it is no surprise that each year there are contributions from countries all over the world. Contributions from South America have been increasing ever since conference inception in 1993, and it is particularly pleasing to note the extensive contributions to this volume from Brazil. Between the Third Biomass Conference of the Americas and this one, two conferences of the parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) occurred. In December of 1997 in Kyoto, Japan, COP3 established a list of mainly industrialized countries committed to a range of greenhouse gas (GHG) reductions by 2008 to 2010. These countries included all 29 countries belonging to the Organization for Economic Co-operation and Development (OECD). The Inter-governmental Panel on Climate Change is investigating how biomass, bioenergy, and the biosphere fit into the question of GHG mitigation. A significant theme of these proceedings is the role of biomass and bioenergy in carbon management. One of the tools with which this issue is increasingly addressed is life-cycle analysis (LCA). Although it originated in the assessment of sustainability - a theme that came into prominence with Agenda 21 of the United Nations Conference on Environmental Development in Rio de Janeiro in 1992 - it has become so pervasive that it no longer merits a topic area of its own in this conference series. The major part of the contributions in these proceedings fill in the intersections of two vectors: the applications of biomass and bioenergy, and the production chain from biomass to bioenergy. Applications of biomass can be seen in six major categories: Daily Living - cooking and space heating at the household level Community needs Industry captive uses of bioenergy Materials and chemicals uses in conjuction with energy production or substitution Environmental Services Secondary energy forms such as electricity and biofuels that carry biomass derived energy from the rural and forestry sectors to the increasingly urban populations of the world The production chain addresses biomass resources, feedstocks, and their conversion to heat, biofuels, and value-added products. The theme of these proceedings is that biomass is a growth opportunity in green energy and value-added products. The papers detail how the modernization of the biomass energy sector, which started with the energy crises of the 1970s and 1980s, is now starting to mature. Novel processes such as fast pyrolysis, which did not even exist before 1970, are now reaching the market place. Biomass has moved from being merely a proposed energy source to being an advanced and modern one. Many elements of the biomass and bioenergy production chain that were proposed a decade ago are now in these pages as on-going demonstrations. Demonstrations of short-rotation wood crops as fiber and energy sources are reaching large scales; technology demonstrators of both electricity and liquid fuels production are also widespread and are detailed here. Major biomass and bioenergy and value-added-materials implementation programs are underway or about to start in many areas of the world. The experiences of those programs currently underway are recorded in these proceedings, and the analysis of these experiences is a major contribution to be found in these volumes.