For patients with advanced cancer, a period of illness and treatment precedes at the end of life. The medical treatment and care that patients receive at the end of their life should be appropriate and in concordance with their goals and preferences. Advance care planning has thus been developed to support patients in planning future medical treatment and care. It appears that patients who have participated in advance care planning are able to talk about good life and for what they are hoping. Topics that confronted patients with physical decline and end of life are more difficult to discuss. Nevertheless, patients who participated in an advance care planning conversation find these helpful and informative. Healthcare professionals are aware of the effort, but know the added value of advance care planning mainly because the patients’ perspective is discussed. Healthcare professionals experienced that conducting advance care planning conversations using a script can help to make it easier to discuss also the difficult topics with their patients. At the same time, using a script can often clash with their usual approach. Thus, training and experience can support them conduct these conversations in a way that adds value for patients. A common view is that patients must be ready for advance care planning. This study shows that "being ready" should not be seen as the starting point. Instead, it is important to be sensitive for signs of "not being ready" to discuss a particular topic, and to realize that patients are able to continue the conversation after a difficult topic.