file permissions with samba

I am wondering if there is a way I can setup permission on directories in the directory that I have setup for samba shares so that no one can move or delete them. The problem I am having of late is that someone from within windows will move the directories around . I think they do it not knowing they are doing it. Its happened several times of late now. I have always found the missing directory nested into another directory in the samba shares. thanks for any info. I am running just in workgroup setup with samba here no domain in the picture. jack