Horizontal traceability

Horizontal traceability shows relationship among related items such as between requirements itself. It traces dependent items within a development phase. Vertical traceability is a characteristic identifying the source of requirements typically from requirements to design, to the source code and to test cases.

Horizontal traceability is an aspect identifying non hierarchical similarities, mutual properties, interactions, etc. among requirements and work products. For example assume we want to implement a login function in four different types of browsers. There are four sub teams to do this. Here the functional requirement remains the same. If any change in requirement happens, then it needs to be reflected across all the four browsers. These kind of dependent requirements are easily traceable if horizontal traceability is marked among them.  QN HT 1To make it more clear horizontal traceability is a sibling kind of relationship while vertical traceability can be treated as parent-child relationship.


Both horizontal and vertical traceability can be bidirectional. Establishing and maintaining robust vertical and horizontal requirements traceability helps to trace transmission of a change to all affected work products and customers/users. When a change in requirement happens, effective impact analysis is possible with the help a traceability matrix. Thus we are in a better position to find adverse side effects due to a modification in a work product and ensure that the change did not hinder compliance with user requirements.


Akhila is the founder and sole contributor of wordsandnotion.com and qualitynotion.com. By profession she is a software Quality and Quantitative data analyst. She is a self motivated life long learner who loves to decode signs from the universe. Her weirdness is totally aligned with her real life stories and thought experiments. She is the author of “Know them, One answer to many questions” (a General Knowledge book) and “I Had a Crush - The 17 Kinks” (A free ebook of 17 short stories)

You may also like...

One thought on “Horizontal traceability

Leave a Reply