This chapter illustrates the use of mono- and polyclonal antibodies as diagnostic tools for neuroendocrine neoplasms of the larynx on the basis of data from the literature and the authors’ personal experience. It is suggested that a panel of antibodies should be adopted, rather than to rely on the specificity and sensitivity of a single marker. It is also emphasized that immunohistochemical methods should serve not as a substitute but as a useful adjuvant in evaluating the morphological criteria of these neoplasm