In your original post, you said you had a web form, which when submitted would be emailed to the members of an organisation for their consideration or whatever.
To send an email you need to specify:
- The Recipient
- The Sender
- The Subject
- The Message Body
You also have the option to specify headers. In the headers, add:
Reply-to: something@getdata.com
With the address being perhaps a mailing list address for the organisation members, but not the original sender.
Googling PHP email headers, and reply-to fields should give you more information also.
Essentially, a reply to address is a default address for replying to which can be different to a from address.
R