Three documents released since July 26, and a recent public hearing, highlighted the difficulties of promoting promising new nanotechnologies, protecting public health and safety, and safely disposing of waste products from their use and manufacturing. Nanotechnology involves manipulating matter the size of one-billionth of a meter or 100,000 times smaller than the width of a human hair. In 2005, more than $30 billion in nanotechnology products were sold globally, according to the Project on Emerging Nanotechnologies (PEN) at the Woodrow Wilson International Center for Scholars.