KAREL ANNE TIESZEN and Kay Kienast have been banging away at the glass ceiling for years. So far, it's been relatively shatterproof.

So they decided to get help from Doug Sokolosky, one of the many executive coaches who have popped up in recent years.

Mr. Sokolosky, a former IBM executive who specializes in coaching women, uses information given by his clients to analyze their work styles and those of key executives around them. He sets up role-playing sessions, acts as a sounding board for clients' ideas and prepares them for performance reviews.

Call him rent-a-mentor.

It's a concept with considerable merit, particularly in a corporate world that has difficulty coming up with mentors for talented women. ``Everyone who's made it has been attached to some coach or mentor,'' says Dr. Kienast, who is in charge of strategy and planning for Digital Equipment's multivendor customer services world-wide.

But while more and more women push into lower- and middle-management levels, there are still few who break through to the upper reaches. ``There are fewer promotable positions in these flatter organizations and more people competing for them,'' Mr. Sokolosky says.

SO HERE ARE some lessons from two women struggling for success in the '90s:

Ms. Tieszen, a computer analyst for Texas Utilities, has management aspirations that have gone unrequited after investing 13 years in the company. ``I feel that I'm waiting for the promotion I've deserved for a long time,'' she says.

So about a year ago, she enlisted Mr. Sokolosky's aid to define the ``glaring obstacles'' in her career path. For example, he helped her realize, ``I'd give credit to everyone, diminishing my accomplishments,'' she says.

Mr. Sokolosky also helped her eliminate the technical jargon from the accomplishments she listed in her latest performance review, taught her to pick her fights more carefully and, perhaps best of all, taught her how to ``read'' her bosses. ``My job is to know what they will listen to and present it in a way they can hear it,'' says Ms. Tieszen.

Dr. Kienast has worked with Mr. Sokolosky off and on for several years, through stints at Dell Computer and Bell Atlantic, before she joined Digital two years ago.

``When you're young, you have this feeling that if you just do the job well, you'll win the game,'' she says. ``As a woman, you have to understand that there's a team, and you have to learn how to play on that team.''

Mr. Sokolosky taught her how to cut her losses on a project gone sour and when to keep her mouth shut. ``I'm very blunt,'' she says. ``With a lot of people, that doesn't work.''

He also pushed her to pursue challenging projects. For example, she might schedule lunch with the head of a coveted project, ostensibly to brief him on something else. ``But my agenda would be to weave in that I did such and such at this other organization that relates to his project and we found that this worked better. That's my opening.''

Some other glass breakers:

Violate the unwritten rules at your peril.

Unwritten rule No. 1: To reach the top requires sacrifice and long hours. If that's your ambition, forget things like balancing work and family. ``Every corporation says it's trying to accommodate women through things like flextime,'' Mr. Sokolosky says. ``The truth is, when you close the door and say, `Who's going to run the next region?' those kinds of things come into the decision making.''

You don't have to be one of the guys, but it doesn't hurt to find some common ground.

ONE OF HER BOSSES is a fanatic about war re-enactments, Ms. Tieszen says, so she always mentions it when she hears about one. Nothing wrong with an icebreaker to make people comfortable.

Brush up on your presentation skills.

Deserved or not, many men perceive women as being uncomfortable in front of groups. ``If you come across as weak, you'll never be perceived as someone able to lead a department,'' Dr. Kienast says. ``The way you dress, the way you sound, the slides you show, that's all part of the work you are presenting.''

Don't try to do it all.

Women often think they must do more than men and end up spinning their wheels on unimportant assignments. ``Doug used to pound the table and say, `You can't do all these things,''' Dr. Kienast recalls. ``A mentor will tell you to pick the things that give you the most impact and farm the rest out.''

Get in the competition for plum assignments.

``If there's a project to reorganize a division, guys will understand that's important and try to get appointed to that team,'' Dr. Kienast says. ``Women won't even know what's happening. I'd say my real job is to manage this function; if I have extra time, I'll work on this project. That won't move you through the ranks.''

It's also critical to push for assignments where you can demonstrate your decision-making skills and they'll get noticed. Women often get cornered in administrative jobs that rarely lead to big promotions.

Try to find an internal mentor.

Personal coaches can polish your package, but they can't provide the critical sponsorship and protection you get when a top executive takes an interest in your career.