cf_select is a quick solution to create chained or related select field easily.

*** Requirements:
ColdFusion 5, MX and up
Supported browser: Microsoft Internet Explorer 5.5+

*** Usage:
<cf_select name="Required. A name for the form select element."
parent="Other select element which this element's data related to"
formname="Required. A name for the form this element resides"
passthrough="Optional. HTML attributes that are not explicitly supported by cf_select.
If you specify an attribute and value, they are passed to the HTML code generated for the cf_select tag">
<cf_option value="option value" parent="parent value" selected>text content</cf_option>
</cf_select>

*** Examples:
For a complete usage example, please click this link