I understand that relationship attributes are a separate concept to Multiplicity, but I did find a useful video that explains this in detail: However, this takes the worksheet exercise to a new level because those attributes that we are asked to think about tend to make the ER model more complex because they are absorbed into the framework of existing entities. The gentleman that explained the concept in the video then added that if the relationship attribute cannot be added to the entity attributes themselves, then a new table is formed when there is a many to many relationship. Multiplicity, a separate concept, is in fact the guiding concept in this approach. Not so much confusing, but rather complex. If I am to summarise what he said, take the relationship attribute and add it to the entity attribute in a "one to many", add it to any entity in a "one to one" but build a new table in a "many to many", which itself would require another relationship or so. A domino effect. How de we keep it less complex or maybe simple?