What does a khan in Mongolia have to say about communication? How can the insights of a lieutenant in the Austrian Empire be useful to us? Can we imagine that a whale has something to say about the beginning of communication? Do we hear the wisdom of wise men and women all over the world? Their insights and stories are guiding us through this unusual journey. We hear how listening to the gentle voice within us can have a global impact. We will learn about a common ground that enables dialogues based on truth and peace. By understanding the heart of communication, our interaction with everything around us will change. New perceptions will emerge and unfold a deeper understanding and appreciation of all life. The "Invisible Doors" are a journey whith about 150 encounters made into small stories. Those encounters take place in different times and with a wide variety of people. They offer new perceptions and insights about all aspects of communication - even the most unbelievable ones. They can be used as a guide, because every encounter is like a story in itself and offers an insight, idea or a new discovery.