I'm not sure whether this is an issue with my use of cl-who (specifically with-html-output-to-string and with-html-output) or an issue with my understanding of Common Lisp (as this is my first project using Lisp). I created a function to create form fields: (defun form-field (type name label) (cl-who:with-html-output (*standard-output* nil) (:div :class "field" (:label :for name label) (:input :type type :name name)))) When using this function, ie: (form-field "text" "username" "Username") the parameter label seems to be ignored... the HTML output is: <div class="field"><label for="username"></label> <input type="text" name="username"/></div> instead of the expected output: <div class="field"><label for="username">Username</label> <input type="text" name="username"/></div> If I modify the function and add a print statement: (defun form-field (type name label) (cl-who:with-html-output (*standard-output* nil) (print label) (:div :class "field" (:label :for name label) (:input :type type :name name)))) The "Username" string is successfully output (but still ignored in the HTML)... any ideas what might cause this? Keep in mind, I'm calling this function within a cl-who:with-html-output-to-string for use with hunchentoot.