**Preface to "Lignocellulosic Biomass"**

In the last century, the production and energy sectors have been highly dependent on fossil resources. Only in the last few years has the increase in oil prices and the environmental impact caused by some processes of obtaining and using petroleum products motivated a change in the thinking of the industrial sector and public organizations. Currently, more sustainable technologies are gradually being incorporated to produce clean energy and bio-based products that serve as raw materials for transformation or final use by consumers. This paradigm shift focuses on the use of available natural resources for the implementation of more economical and environmentally friendly production systems.

The origin of the concept of sustainable development is not up-to-date, as it was first defined in the Brundtland report published in 1987 ("*Our Common Future*", Brundtland, 1987) and has served to nurture future policies such as the Montreal and Kyoto protocols, Agenda 21, the Millennium Development Goals (MDGs), and more recently, the Sustainable Development Goals (SDGs). These policies not only highlight the problem of energy supply and climate change, but the concept of sustainability encompasses much broader implications, such as food, production processes, agriculture, fisheries, and quality of life.

In this sense, lignocellulosic biomass is a valuable, renewable and undervalued source of chemicals for use in the processing industry and can be used directly or indirectly for the production of platform molecules or bioproducts through chemical, physical, microbial, or enzymatic treatments and can also be used in sectors such as food, health, medicine, energy, materials, and the chemical industry. In maintaining this process, the scientific community plays a very important role in generating the basic knowledge that gives rise to technology and allows developments in the laboratory to be transferred to society. The integral valorization of lignocellulosic biomass is a fundamental pillar of sustainable development. Given the origin of this biomass, as well as its composition, lignocellulosic biomass is a vast resource.

In creating this Special Issue, focused on the valorization of lignocellulosic biomass, we aim to establish an invaluable source of information that will serve as a reference for other researchers.
