Hullo,
Just the fact that you want to put up posters reflects the discomfort you feel about discussing this topic. Being respectful towards the other gender is behaviour which we can learn. Having committees also is successful when the women complain about the incident, discuss it with their superior or HR. It is reactive activity. Harassment is so subtle that many times women who are entering the employment market for the first time, are not able to distinguish between what is allowable and what is not - jokes, sexist comments ...there are a million things which go into determining a gender sensitive culture. Women have to feel comfortable about bringing the incidence out into the open. Perception based stereotypes are part of our cultural upbringing and can be changed.
We have done work in other organizations on stereotypical attitudes, helping participants examine their filters, develop their ability to have gender free conversations and work effectively in teams - Awareness programs, Mentoring programs, coaching women workshops, counselling etc. You can write to me on geet.jalota@gmail.com to know more or if you care to share your email id, I can send you some material on our work.
Thanks
Geet