  Recently, there has been growing attention on behalf of both academic and
practice communities towards the ability of Artificial Intelligence (AI)
systems to operate responsibly and ethically. As a result, a plethora of
frameworks and guidelines have appeared to support practitioners in
implementing Trustworthy AI applications (TAI). However, little research has
been done to investigate whether such frameworks are being used and how. In
this work, we study the vision AI practitioners have on TAI principles, how
they address them, and what they would like to have - in terms of tools,
knowledge, or guidelines - when they attempt to incorporate such principles
into the systems they develop. Through a survey and semi-structured interviews,
we systematically investigated practitioners' challenges and needs in
developing TAI systems. Based on these practical findings, we highlight
recommendations to help AI practitioners develop Trustworthy AI applications.
