What is Psychotherapy?
Psychotherapy is the use of psychological techniques to change behaviors, feelings, thoughts, or habits. It is generally employed to relieve symptoms of emotional or behavioral dysfunction or distress, however it is also used to help people achieve greater levels of self awareness and to actualize latent potential.

Psychotherapy is the treatment, by psychological means, of problems of an emotional nature in which a trained person deliberately establishes a professional relationship with the patient with the object of (1) removing, modifying, or retarding existing symptoms, (2) mediating disturbed patterns of behavior, and (3) promoting positive personality growth and development. (Wolberg, 1977)

Steadman's Medical Dictionary defines psychotherapy as:  treatment of emotional, behavioral, personality, and psychiatric disorders based primarily upon verbal or nonverbal communication with the patient, in contrast to treatments utilizing chemical and physical measures and it defines counseling as:  A professional relationship and activity in which one person endeavors to help another to understand and to solve his or her adjustment problems; the giving of advice, opinion, and instruction to direct the judgment or conduct of another.  (Stedman's Electronic Medical Dictionary, 1994)

Psychotherapy is a set of techniques intended to improve mental health, emotional or behavioral issues in individuals, who are often called "clients". These issues often make it hard for people to manage their lives and achieve their goals. Psychotherapy is aimed at these problems, and solves them via a number of different approaches and techniques; commonly psychotherapy involves a therapist and client(s), who discuss their issues in an effort to discover what they are and how they can solve them. Because sensitive topics are often discussed during psychotherapy, therapists are expected, and legally bound, to respect patient privacy and client confidentiality.

When should one go for psychotherapy? 
Psychotherapy is recommended for individuals experiencing symptoms of psychological distress related to relationship problems, life stressors, etc. If you are depressed, anxious fearful, angry or don't feel in control of your life psychotherapy might be helpful to you. If you are unhappy, having relationship problems, or feel you are not living up to your potential psychotherapy can give help develop greater self awareness and support your efforts in improving your life.
If you are unsure about starting psychotherapy, consult a mental health professional for an assessment and evaluation to help in making the decision about whether to engage in psychotherapy and what kind.

Who does psychotherapy? 
Psychotherapy is practiced by a number of different mental health professionals. Although they have similarities in their approach to treatment, their varied training backgrounds sometimes lead them to choose different approaches and/or orientations.  Psychotherapy is conducted by a license professional.  Psychotherapists may be psychologists, master’s level practitioners, and psychiatrists. 

In most countries psychotherapists must be trained, certified and licensed with a range of different licensing schemes and qualification requirements in place around the world. Psychotherapists may be psychologists, social workers, trained nurses, psychiatrists, psychoanalysts, or professionals of other mental health disciplines. Psychiatrists' training focuses on the prescription of medicines, with some training in psychotherapy. Psychologists have special training in mental health assessment and research in addition to psychotherapy. Social workers have special training in linking patients to community and institutional resources.

Recent trends in drug development to treat chemical imbalances have led to a more wide spread use of pharmaceuticals in conjunction with psychotherapy by medically qualified mental health nurse practitioners, psychiatrists, and in some states prescribing psychologists. Medications have benefits for patients with ailments such as bipolar disorder, impulse problems, schizophrenia and obsessive compulsive disorder, depression, anxiety, attention deficit problems, aggression, etc.  Your psychotherapist is trained to communicate, with side release for confidential information, with your psychiatrist to help monitor symptoms and side effects as those relate to medication management. 
There are a wide variety of psychotherapeutic modalities (e.g. individual, group, family) and theoretical approaches (e.g. psychodynamic, behavioral, existential, cognitive).  There are at least five main systems of psychotherapy:  psychodynamic, cognitive and humanistic/supportive, behaviorism, and brief counseling.

There are a variety of treatment modalities or forms available to meet each patient's individual needs. The modality chosen will depend on factors such as diagnosis, age of the patient, family support, financial constraints and patient preference.  

Individual Psychotherapy is the modality with one patient and one therapist. This form offers the most attention to the patients individual concerns however it can be limited in that it cannot directly study family or social relationships. There are many different styles or theoretical orientations of therapists such as psychodynamic, cognitive and behavioral.

Family Psychotherapy is conducted with all or as many members as possible of a family. The work may all be done with the entire group or involve various combinations of family members. The process helps identify and modify maladaptive or destructive interaction patterns as well as foster group communication and problem solving skills.

Group Psychotherapy is conducted with at least three and up to fifteen patients together. This modality offers the patient the opportunity to interact with others and learn from them as well as study their own relationship style. Patients usually encounter some social anxiety in beginning group therapy, however it offers an ideal environment in which to challenge such anxieties.
Homogeneous groups are made up of individuals with similar concerns such as chemical dependency or women's issues. These groups offer support and understanding and the feeling that one is not the only one struggling with a given set of concerns.
Heterogeneous groups have a more varied membership and more closely approximate the world at large.

Marital/Relationship Therapy is conducted with couples in a marital or "significant other" relationship. Its purpose is to assist the couple to work together as partners to communicate, love and solve the problems of daily life. The establishment of realistic, adult expectations is usually an important goal.

Stress Management training is a process of identifying stressors, learning ones physiological and cognitive responses to stress and developing techniques to manage those responses. Common stress management techniques are systematic desensitization, relaxation training, and cognitive therapy.

Medication Management is the use of psychotropic medications to manage emotional, cognitive, and behavioral symptoms. The medication is prescribed by psychiatrists after thorough evaluation and with ongoing monitoring. Medication management is usually implemented in conjunction with other therapies aimed at treating the underlying causes of the condition.