When a materials issue arises the key deliverable is to find the root cause of the problem any way you can. There are many techniques that can be used in these situations and it is unlikely that limiting oneself to one methodology will be sufficient. Keeping this in mind, surface analytical techniques such as X-Ray Photoelectron Spectroscopy (XPS), Time Of Flight Secondary Mass Spectrometry (TOF SIMS) and Auger Electron Spectroscopy (AES) are critical tools in the semi-conductor industry providing information about interface composition and structure, root cause analysis for delamination issues and identification of low level contaminants. The tutorial will provide an overview of XPS and TOF SIMS basic methodology and then cover some specific examples of the techniques in action. The advantages and pitfalls of these analyses will be discussed along with how one decides what particular experiment needs to be carried out. TOF SIMS and XPS have proved to be particularly symbiotic in assembly related issues: TOF SIMS gives high sensitivity, good spatial resolution and swift data but it is very hard to quantify and often very difficult to interpret whereas XPS is more quantifiable and generally more easy to understand (unless you get very subtle) but has less sensitivity, spatial resolution and is very slow in comparison.