A case may be made or lost on the basis of a microscopic piece of hair. The recent focus on DNA evidence has cast a shadow over the importance of collecting trace evidence that may be too small to see with the naked eye. In many cases there is either no DNA evidence to collect or the DNA evidence is useless because there is nothing to compare it to. Max Houck is a forensic anthropologist and medical examiner who worked on over 800 cases at the FBI laboratory in Texas from 1992 to 2001. He has edited two books on trace evidence and his expertise is used throughout the article to underscore the importance of trace evidence and the care it takes to collect it properly. Five examples from Houck’s books of the importance and usefulness of trace evidence are presented. In the cases, investigators used dog hair, fiber-plastic fusions, soil, hair and fiber, and gastric secretions to piece together the stories of crimes. One of the most important things about trace evidence is how it is collected and handled. All evidence of a crime is based on the principles of transfer and persistence. Evidence, especially trace evidence, must be handled with extreme care to avoid dislodging and losing trace evidence and to avoid transferring trace evidence from one thing to another. The article discusses the responsibilities of the first officer at a crime scene in terms of securing the scene and preserving evidence. Finally, Houck points out that trace evidence should be the first thing examined in a forensic laboratory because if it is not tested first, it may be lost or rendered useless because of the excessive handling. In conclusion, Houck advises officers to think very small when it comes to trace evidence; it may make or break a case.