As a wall restoration and pointing company, this would fall under the type of work that we do day in day out. Most exterior cracks are relatively easily tackled (without the need to rebuild areas of the wall) and are often as a result of minor movements consistent with the age of the property or can be linked to alterations such as the fitting of Double Glazing.
Typically a combination of wall ties and crack stitching bars can be used to strengthen the area of the external wall prior to repointing.
In this particular instance cracks in the inside of the property have been reported and if in the vicinity of the outside cracks there may be a bigger issue affecting the property. The use of a structural surveyor is often prudent where the issue is deemed to be a significant structural issue. Once a Structural Surveyor has been appointed, builders will normally follow the advice of a surveyors report and/or structural engineers drawings regarding how to go about the repair.