One of the most common changes people make when renovating a home is to open up the wall between the kitchen and an adjacent room. The extent of this "opening" can range from a simple pass-through to complete removal of the wall. Creating a visual connection between two rooms can often help make both roms fell larger - longer sight lines give the appearance of additional space.
When removing walls, it is critically important to understand the structural implications. Interior walls may be load bearing, meaning they provide structural support to some portion of the building above. In cases like this the wall can still be removed, but a beam must be installed to carry the load once carried by the wall. Your architect or structural engineer can take responsibility for designing a correctly sized beam.
You may run into a problem retaining enough counter space and cabinet space when you remove a wall in your kitchen. This example provides one solution to this problem - a kitchen island.