I have searched in vain to see if (and how) a tag can be added to an image while viewing the image.

Or is this something that must be done somehow in batch?

Thanks for any assistance.

PS I am extremely impressed with Zenphoto - an excellent piece of software! Bravo to the developers!

Thanks ;-) You cannot add tags on the front end directly. Several ways:

1. On the front end you can use the admin toolbox and it's "Edit image" link for quick access.
2. On the backend within an album on the images list tab you see a "Edit all image data".

3. You can also use the bulk action on the images list and on the images order tabs

4. Alternatively you can embed tags via Exif / Iptc meta data into the images before uploading them.

Thanks (again) for your help.