• Developing an Assertive Style
  Assertive behaviour is about expressing your feelings, thoughts and wishes, and standing up for your own basic rights without violating those of others. It’s about saying what you mean and having self-respect and respect for others. Assertive is a skill you can acquire, it is not a personality trait. You may find it easy to be assertive with strangers, but very difficult with your family or work colleagues. To act more assertively particularly in difficult or stressful situations, then you need to acquire a positive self-image and to believe that you can act effectively.

• Why behave assertively?
  The ability to express feelings and to be open to others about what you want, maximizes the chances of your desire to get more what you want. If you are usually passive, you are likely to get trampled on by other people and this will lower your self-respect and self-esteem.
  
  Passive behaviour is often related to a sense of powerlessness and feeling you can have no influence over what happens. You do not achieve your goals as you allow others to choose for you. You rights violated and you are taken advantage of. 
  
  Assertive behaviour means that you
• Allow others to complete what they are saying before speaking
• Stand up for the position that matches our feelings or the evidence
• Make our own decisions on what we thinks is right
• Face problems and decisions squarely
• Face responsibility with respect to our situation, needs and rights
  
  So it is important to be assertive not only to get more of what you want but also to feel better about yourself and your behaviour.
  Everyone has the right (1) to hold and express different views from other people (2) to be listened to and taken seriously (3) to say ‘No’ (4) to disagree (5) to be treated with respect (6) to admit ignorance (7) to set their own priorities (8) to express anger (9) to have privacy (10) to be wrong.
  
  First rule of Assertiveness
  1. Know others have rights
  2. Decide what you want to say and say it clearly and concisely
  3. Be prepared to change your mind
  4. Look for a win-win situation where appropriate

(Source : Interpersonal Skills, Astrid French)