You may be eligible for a government program such as Medicaid at little or no cost. Call your state's local social services office for details. If you are not eligible for a government program, Blue Cross plans in most states have a yearly "open enrollment" period. You can't be turned down for this coverage if you pay the premium. Some states have "high-risk pool" programs in which you are assigned to one of several plans. This also requires you to pay a premium, but the state may help fund it.

Did you have coverage within the last 18 months through your own or your spouse's private employer? If so, and the employer has at least 50 workers, you can buy what's called COBRA Continuation coverage. You pay the plan's full premium plus a 2 percent fee. COBRA coverage is a better value than an individual or high-risk plan. Contact your former employer for details.

No specific plan is best for everyone. The three most important issues are the health services covered, the choice of providers, and the plan's cost to you. These issues are discussed in the next few answers.

You also should consider whether the plan will cover just you ("self only") or-if you have a family-them as well (a "family" plan). Finally, a plan offered through a "group" such as your employer usually will be a better value than an "individual" plan.

Each plan has different rules for the services it covers. Most plans pay for doctor and hospital treatment for asthma if the provider is approved by the plan. But many plans limit coverage of asthma medications and medical equipment. And only a few plans-mainly "Health Maintenance Organizations"-cover preventive care.

In addition to rules specifically for asthma, plans may have rules applying to several medical conditions. Two frequent rules are pre-existing condition limits and chronic condition limits.

A pre-existing condition limit means that if you already have a medical condition when you sign up for a plan, the plan will limit its payments for that condition for a certain time. Some "individual" and "small group" plans have this rule, and it can be a major problem for people with asthma. Government plans usually don't have this limit and, if you change plans that are employer-sponsored, the rule generally can't be used if the employer has at least 50 workers.

A chronic condition limit means that if a medical condition is not expected to show improvement within a certain time, then services for it won't be covered. In rare cases, this can apply to asthma.

Almost every plan has a list of "approved" providers the plan will pay best, while some plans pay nothing to a "non-approved" provider. Most or all of a plan's "approved" providers are listed in its "Provider Directory." You can get a copy by asking the plan.

Because you must pay more to use a non-approved provider, the larger the plan's approved list, the better. But provider choice isn't just about saving money. Some providers specialize in treating asthma, some are located near you, and so on. Usually, managed care plans have the fewest approved providers.

There are three types of managed care plans: preferred provider organizations, health maintenance organizations, and "point of service" plans. A preferred provider organization (PPO) allows the patient to choose any provider, but pays approved ("preferred") providers a higher amount than non-approved providers. The plan might cover all of a PPO doctor's charge but only 80 percent of a non-PPO doctor's bill.

A health maintenance organization (HMO) pays nothing for non-emergency care if from a provider lacking a contract with the HMO. So an HMO patient has a strong financial reason to use only HMO providers. An HMO also requires you to choose a "primary care" doctor. He or she must approve referrals to "specialist" providers such as pulmonology doctors and respiratory therapists.

The third managed-care plan, called "point of service" (POS), is a cross between an HMO and a PPO. Like an HMO, it requires you to choose a primary-care doctor. Like a PPO, if you want to see a non-HMO provider, the plan will pay some amount for that care, but less than if you used an HMO provider.

Compared to traditional insurance, managed care plans are cheaper or offer more benefits. But they always have fewer choices of providers.

You may have to pay four types of costs. These are:

• Premiums (periodic fees charged regardless of how many services you use).
• Deductible (yearly total amounts you must pay for one or more services before the plan will begin paying).
• Copayments (small amounts you pay each time you get a service).
• Uncovered out-of-pocket costs (your spending for services the plan doesn't cover, in contrast to premiums, deductibles and copayments).

Most plans have a "catastrophic," "stop-loss" or "hold harmless" feature that limits the total yearly amount you must pay. But that cap doesn't apply to the premium. The higher the total premium, the lower the other three types of costs.

Many people prefer to pay a higher premium to reduce their other costs. That protects them from large unexpected bills. It's especially good if you're likely to get many treatments for a major medical condition.

What is best depends on your situation. Because you or a family member has asthma, it's good to have a plan with broad coverage for that condition. But you may not be able to afford a high-cost plan.

If you've long been treated by a doctor who's not contracted with any plans, you'll need to get a non-managed care plan to keep that doctor. But if you just moved to a new city, being able to see a particular provider is not as important. Your doctor's staff or a community group such as a senior citizen association can advise you what plan is best.

Assignment of benefits ("assignment" for short) means your provider agrees to send a claim to your plan and accept the plan's "allowed" payment as full payment.

You don't have to pay out-of-pocket for the entire bill when you're treated. You also may save money and you don't have to mail a claim. And if the claim is denied, your provider usually can file an appeal on your behalf.

All providers contracting with managed care plans, and all Medicare and Medicaid "participating" providers must accept assignment for those plans. But some providers whose services are in high demand don't accept assignment because they can pick and choose the patients they treat. Assignment is always good financially, but it doesn't concern the quality of your care.

It's not good to pay the full premium of more than one plan. The plans usually will duplicate each other but you won't be paid double. Yet sometimes having two plans makes sense.

If you have a plan such as Medicare that has major limits, you can buy a supplemental plan such as "Medigap." If both spouses in a family have family plans, each plan may cover limits in the other.

There are three "dual coverage" rules on which plan pays first. Some plans (e.g. Medigap) always pay after another plan (e.g. Medicare). Read the plan's rules to determine which plan pays first.

If you and your spouse both have family plans, your plan will always pay first for your own care. Your spouse's plan will pay first for your spouse's care. After the first ("primary") plan has paid, if there's any unpaid balance, the other ("secondary") plan should be billed.

When there are two family plans and a child is treated, the "birthday rule" usually applies. The plan of the parent with the birthday earliest in the year will pay first. If the mother's birthday is January 2, and the father's is June 7, the mother's plan would pay first for the child's care. But plans in a few states use different rules.

Different plans have different "appeal" rules. It's important to know these rules because if you don't follow them, your problem won't be solved. In some plans, you must appeal in as little as 30 days.

You're entitled to a pamphlet summarizing your plan's rules. This "insurance policy" booklet is called an Outline of Coverage, Summary Benefits Plan Description, Medicare Handbook, or similar name. You should read this. If you don't have it, you can get a copy from your plan.

Government plans such as Medicare and Medicaid give you many rights. They usually allow you to appeal several times if you disagree with a decision.

Private plans are run by insurers such as Blue Cross. Their rules are less detailed than government plans. You become eligible for a private plan if you or your spouse's employer offers it or if you pay individual premiums.

Some private plans are allowed to turn down your enrollment even if you can pay the premium. Private plans may be either "true insurance" overseen by your state government or "self-insured" plans. Self-insured plans give you fewer appeal rights. In general, plans sold to individuals and to small companies are insured plans. Those sold to large employers are self-insured. If your plan booklet does not say which type it is, contact the plan or your state's insurance commission in your state capitol.

If a claim is denied, the Explanation of Benefits notice you get must give a reason why. Some reasons are easier to overturn than others. If the plan says your care wasn't "medically necessary," that's a poor explanation and often can be reversed.

If your care went beyond what the plan covers, such as medications costing more than the plan's $500 yearly limit, it's unlikely the plan will reverse its decision. But it may do that if you convince the plan it would save by avoiding bigger costs. For example, asthma medication may keep you from going to the hospital. The plan doesn't have to make exceptions. When it does, that's called an "extra-contractual" benefit.

If you have a question about your plan, call the plan's customer service department, using the phone number on your enrollment card or plan brochure. Your employer's benefits office, your local labor union or a consumer advocacy group can help.

Your doctor or hospital office also may help, especially for a denied claim when the provider accepted assignment. And you can contact your state's Insurance Commission in your state capitol.

If you follow all the rules and still have a problem, you can hire a lawyer. The lawyer can sue the plan for "breach of contract." But that is expensive and you aren't likely to win. This is why some people think the laws should be changed to give patients more rights.

Health insurance is valuable, but many problems can occur. It is important to be well informed so you can get the kind of insurance you want and pay less for it.