First and foremost. As the term "engineers" is very broad in our books, However to the public the consensus is that all we do is tinker with machinery or something of the sorts. It is also very hard to convey the significance of our role in society as well as the technical concepts to them if one does not have prior technical knowledge or background. This may lead to a lose in interest when conversing to the other party and they may take it for what it is.