You get one of those annoying phone calls offering you the deal of a life time, you respectfully cut the call short and go back to eating your dinner. You've just set a boundary. A feeling of entitlement helps you to understand that how you use your time (irrelevant phone call or enjoying your dinner) is a choice that you get to make and then communicate. Boundaries make it more clear where you end and I begin and visa versa. Healthy boundaries help you know who you are. That's important as you interact with other people.
Boundaries come in assorted forms. Physical boundaries can involve how close someone can come to you before you start to feel uncomfortable. There are assorted factors that will influence this. Comfort or lack of it may involve things such as the physical size, shape, and volume (as in loud/soft voice), or gender of the other person. You're likely influenced by how well you know the other person and how much safety or trust you feel with him or her. The latter is an emotional aspect of boundaries.
Boundaries also involve mental, psychological, and even spiritual issues and are influenced by culture, personality, life experiences, roles and so forth. These influence how much of yourself you share in terms of your thoughts, feelings, and even physical intimacy. It becomes clear that defining the term boundaries can involve physical, emotional, mental/psychological and spiritual dimensions and there's considerable overlap. It is also important not to limit the discussion or definition of boundaries.
How do we acquire our boundaries and entitlement to communicate them? If a baby is cared for by a parent or parental figure who is emotionally present and offers physical and emotional nurturing, the baby learns to develop trust in the parent. This is an important learning task of infancy and childhood. The child's needs are heard and attended to. If the baby is hungry and cries, the parent responds with food and the cuddles that go with the food. If the parent is distracted with her/his needs for an extended period and repeatedly, the message to the child is, "My needs are more important than your needs" . This can happen in homes where the parent is frequently inebriated, seriously physically or mentally ill, emotionally numb, and so forth. When an infant's needs are met, the child learns to trust her/him self and this is the beginning of learning boundaries and the right to express needs and boundaries. The child whose needs are repeatedly ignored learns to stop listening to him/herself. This interferes with the development of healthy boundaries. Some childhood examples may clarify how learning healthy boundaries can be interfered with. The child who feels sad and cries and is told "Stop crying or I'll give you something to cry about" is sent a message that sad feelings are not allowed and certainly not allowed to be expressed. That child as an adult may have a difficult time expressing a boundary that involves their (sad) feelings. Consider a child who yells "Stop, Stop" while playing with a parent who is ticking her/him. The parent ignores the cries and continues to tickle. The message to the child is, "You don't get to decide when who does what to you body". This is a mild example and would have to occur repeatedly for a child to have their boundary learning interfered with. Take a more dramatic example of the child who is repeatedly physically or sexually abused. This child learns that they must ignore their instincts that tell them that the abuse is not ok. Additionally, they learn that they have no right to set boundaries or limits even about their own bodies. Childhood learning set the stage in numerous ways for adults who have a clear idea about their own boundaries and their right to communicate them. An articulate sense of self, hopefully cultivated during childhood, is the basis for healthy boundaries. For adults who weren't lucky enough to acquire healthy boundaries in childhood, the challenge is bigger. They may tend to be too rigid in setting limits which reflect boundaries or they may go to the other extreme and have very few boundaries. It's probably most useful to see boundaries as a continuum, rather than polarized as having all or having none.
Lets consider a few ways that an adult can expand her/his healthy boundaries. Problem ownership is a good place to begin. If a problem or issue arises, first one needs to decide who it belongs to. Does the problem/issue really impact you? Does your teenager's messy room really impact you or can you just close the door? If your teen left the family room in a mess and you and your friends want to watch videos, this impacts you directly. You need to be involved in setting a limit and communicating a boundary. If you feel frustrated because your friend rarely brings enough money when you two go out to lunch, is this really your problem? If you buy her/his lunch and thus avoid stating a boundary ("I am not comfortable paying for your lunch") are you rescuing instead of looking after yourself and setting a healthy boundary? A positive first step in healthy boundaries is deciding if the problem belongs to you. If it does, you have some responsibility in working on a solution which likely involves boundaries.
We see from the examples above, that being able to say "No" is a vital part of healthy boundaries. Before you can say no, you have to feel that you have a right to say no. This is entitlement. Watch out for guilt. It's often one of those old habits that says, "Ignore your needs and feelings and just take care of the other person". Guilt can really get in the way of building healthy boundaries. Other people sometimes use guilt to get you to ignore your boundaries.
Healthy boundaries involve an awareness of self. They also require an ability to match self with appropriate boundaries. If one becomes misguided this can become an issue about power and control. It's important to balance flexibility with firmness. Consistency and clarity will be very useful. It's likely that expanding healthy boundaries will be a work in progress and may need to evolve as you evolve as a person.
Parting words: Get to know you. Listen to you. Take care of you. This is done within a context of respect for self and respect for others with integrity and flexibility.