Introduction Hands-on Inquiry Based Science Education is being developed in México, United States and many other countries as a key educational strategy for the XXI century. This form of science education has a strong impact on the kind of opportunities given to people and society, through building scientific skills and developing the capacity of learning, team work, and intelligent and active problem solving participation of children. The Inquiry Based Science Teaching Systems generate a new motivating context of learning in schools with the purpose of achieving a better development of learning in both students and teachers. In an Inquiry approach, students manipulate, explore, share and get involved in their own responsibility for learning. To work with an Inquiry system in classrooms requires materials, guides for the hands-on activities and specifically an engaged, motivated and enthusiastic participation of teachers. Professional Development of teachers and an appropriate training strategy to provide high quality teaching of science in basic education are key issues to ensure the success of the Hands – on Inquiry based systems to guarantee the right cognitive development that is expected of children. The main objective of the Third International Conference on Science in Basic Education, to be held in Monterrey, Nuevo Leon, Mexico on March 2005 will be to identify the challenges and necessities that we have in this important field. To analyze the necessary elements that bring opportunities of high quality professional development for teachers that work with Hands on Inquiry Based approach. The conference will gather recognized researchers, teacher training specialists, professional development experts, and distinguished members of government, business and academic communities from the United States, England, France, China, Sweden, Chile, Colombia, Brazil and Mexico; to share their experiences on design, assessment, and follow up of their programs. The conference is possible thanks to the support and collaboration of the National Secretary of Education in Mexico, The National Academies and the National Science Resources Center in the United States, The International Council Science Union, The Inter Academy Panel and other National and International organizations. Previous to the Conference two preparatory meetings will be held, one in Mexico City (November 2004) and another in El Paso, Texas (January 2005) to analyze the main challenges and necessities with a regional perspective.