Q: What is the best way to be a new step-parent of a teenager and a school-age child?

A: If I were to write a want ad for a step-parent, it might look something like this:

Challenging Lifetime Opportunity in Step-Parenting

Marry me and help me raise my children from my first marriage. I am looking for someone who is patient, kind, and fun. Requirements include someone who is not insecure or overly sensitive. You will be forced to socialize with people who might not like you. It will take time for the children to listen to you. Hours: 24/7. Please call: 555-555-5555.

How many of you would apply for that job? Yet, many people remarry each year. Few know, however, what the job really requires. As a therapist and proud and happy step-parent, I have learned the rewards and responsibilities of helping raise and care for another person's child. Good step-parenting rests on you and your new spouse or partner becoming a team. But how do you do that? The scenarios below are examples of typical problems:

1. Marie is a willful and fretful 8-year-old. Her father Richard recently married Annette, a woman whose one child from her previous marriage died from cancer. One night, less than a month after the wedding, Richard had to attend a meeting at work. He leaves Annette in charge of cooking dinner for Marie, and making sure that Marie takes a shower. While Annette makes Marie's favorite dinner of grilled cheese sandwiches, she asks Marie to take her shower now so that by the time she is finished, her dinner would be ready. Marie stomps her feet, and says: "No. You're not my mother." Annette didn't know what to say or do.

What are the problems? What should Annette do?

Richard's first mistake was not establishing with Annette rudimentary ground rules about parenting and step-parenting. Richard wanted Annette to assume many parenting responsibilities, but they never talked about expectations. As a result, Annette didn't know her role, and Marie didn't know it either.

If Richard and Annette had discussed step-parenting and explained it to Marie, then Annette could have said something like this to Marie: "I know I'm not your mother, but I love you, and I'm responsible for you, so could you please take your shower."

2. Elena has a 13-year-old daughter, Louisa, from her first marriage. Louisa is a very studious and bright teenager who skipped a grade in school. But, as her mother described her, Louisa can be very lazy, entitled, and angry at home. Louisa is an only child, and she dislikes having to split her time between her divorced parents. Less than three years after Elena's divorce, Elena married Edward, a man with adult children who have graduated college, and who live in other cities.

Lately, ever since Louisa's school work has become more demanding, she has become more irritable. Louisa's teachers say that she is not working up to her potential. As a reward for good grades and reports in the future, Elena bought her a cell phone. Louisa's grades and effort improved. However, Elena said the house rules are that she still cannot use her phone at home until all her homework is done and has been checked by Elena.  lena said that Louisa can have a snack before dinner, and then go to her room to do her homework.

One late afternoon, while Elena is at work, she gets a call from Edward. He says that Louisa is not doing her homework and that she is talking to her girlfriends on her cell phone. Edward says that Elena has to take the phone away from Louisa as soon as Elena comes home. Elena can barely contain her frustration with Edward. She says to Edward, "Why can't you just take the phone away from her?"

How would you handle this problem?

You could resolve this issue in two ways. If Elena and Edward had established parenting guidelines and communicated them to Louisa, then Edward could have sat down with Louisa so they could go over her homework together. Edward would then have the responsibility and the power to decide whether to grant the phone or take it away. Louisa would see Edward as a strong step-parent who is empowered to enforce rules.

On the other hand, Louisa might see her mother's absence as an opportunity to undermine her mother's phone rules. Louisa is willful. If her mother and Edward had not co-established parenting rules and then communicated them to Louisa, the teenager might believe that her mother would side with her. After all, Louisa thinks if my mother didn't say Edward is important I won't see him as important either. Louisa's defiance of Edward is one way of testing his role. In that case, when Elena comes home, she has to do two things:

a.) Explain to her daughter that Edward does have parental power.

b.) Say with Edward to Louisa that the phone will have to be taken away for a certain amount of time that she and Edward will discuss.

3. Tina and Tom have been happily married for several years. Tina, an architectural draftsperson, has 11-year-old twins, a boy and a girl, from her first marriage to Ivan-whom she secretly calls "Ivan the Terrible." Tom never had children, and when Tina and Tom married, even though Tina was approaching 40, she and Tom wanted to have a child. "I wanted to get it right this time," Tina said. They had a son, and everyone seemed happy-except for Tina's ex-husband Ivan who never remarried.

Ivan was so different from Tina's new husband Tom. Ivan had no formal education or skills, and he drifted from one low-level job after another. Tom started his own catering business after college, and he now supplies college campuses with roving catering trucks.

A problem arose when Tina wanted to enroll the twins in two different summer camps-one specialized in science, and the other in art. The twins are very talented, and they would benefit from this experience. Tina is so upset when Ivan says the twins have to spend the summer with him. She is angry, and she and Ivan fight over the issue. She and Tom just bought a cottage on a lake near the camps, and she was looking forward to seeing the twins during the summer. When Tom offers to intervene, she refuses to discuss the situation.

How would you handle this situation? What are the problems?

Tina has not granted Tom a full enough role in co-parenting the twins. She has drawn an imaginary line that separates her two marriages. Many spouses don't want to "contaminate" their new marriage with problems from the old. They fear that the stress will add too much stress to the new marriage and weaken it.

For many couples, however, the step-parent's input can be very valuable. He or she might have a more objective, less emotionally heated view of the situation. A great deal of research in the role of the step-parent concludes that the experience of being a step-parent is often one of being an "outsider" in various ways and degrees. A step-parent often feels they have to have "guts" but get "no glory." They engage in decision-making and caring, but still can remain "second fiddle" in the mind of the stepchild. Tina needs to involve Tom more as a parent and a source of advice. Excluding Tom will increase the stress in her new marriage.

Tina should also put aside her anger at Ivan, and not use it to punish him by leaving him out, too. She needs to work out a plan with Ivan about summers. She could appeal to Ivan's pride in his children's accomplishments.

Tina finally listened to Tom's ideas. The agreement was that Ivan could use the cabin by the children's camps for the first half the summer. These camps allowed parental visits twice during the summer. Ivan would attend the first parent visit.

Of course, every family's situation is unique in its details. Yet, they share most of the basic issues of power, inclusion, and teamwork. Here are some key tips.

1. Develop parenting guidelines with your new partner. Discuss with your children this new person's role.

2. Be flexible. Parenting rules change as your children age. No matter how specific the rules that you and your new partner make, realize that they will have to be adjusted.

3. Work with your children's other biological parent, if possible. Don't deliberately exclude your ex from parenting decisions. Don't demand agreement. Instead, find a way to solve the issues with an approach that your ex can experience as a gain. Don't get too rule-bound such as playing a destructive game of "Even Stevens" where you keep score of who got what and when.

4. Remain positive, warm, and calm. No one likes to be threatened or yelled at. If your ex is a sane and reasonable-enough person, your calm style of discussing things might encourage a similar attitude in your ex.

5. Give things time. Children of all ages need to adjust to this new person in their lives. Don't expect or demand them to love this new person or to call this person Mom or Dad. The other biological parent, no matter how unloving or helpful that person might be, is still often recognized as Mom or Dad.

6. Don't expect one big happy family, but work on warm co-existence. Some families truly do become one big, happy-enough family. They include each other at certain holidays, or attend soccer matches, and recitals together. This inclusiveness is often easier on the children. They don't feel trapped in taking sides. You don't have to love your partner's ex. You just have to find ways to get along.

7. Become aware of the ease of adopting a mindset that your previous family was flawed, but the new one is perfect. Children from the first marriage often unconsciously feel flawed or damaged because of their parents' divorce. They tend to blame themselves for the break up.  If the children physically resemble the ex, this negative self-view can be strong. These "first" children often regard their step-siblings as better and more worthy. Make sure you find ways to nurture the talents and love for all your children.

Dr. LeslieBeth Wish, Ed.D, MSS, is a nationally recognized psychologist and licensed clinical social worker, specializing in women's issues in love, life, work, and family. Sign up on her website, www.lovevictory.com, to receive free advice, blog, cartoon, and information about her two upcoming research-based, self-help books for women: The Love Adventures of Almost Smart Cookie—a cartoon, self-help book and Smart Relationships.You can follow Dr. Wish on Twitter.