How should executives who manage corporate technology services guide their careers? The past two decades have seen a vast increase in the pace of technological innovation in corporate settings, with disruptive effects on markets and individual careers.

Consider the pace of technological change in software development and telecommunications the past 15 years vs. the 40 years before. Mid-century professionals in each of these industries would find the past decades’ pace of change dizzying:

IT - Infant to Young Adult: In 1964, IBM released the System 360, the first computer product line with a consistent, scalable architecture, and launched the “golden age” of mainframe computing. Many innovations followed, including online processing and relational databases. Still, a mainframe computer programmer who entered the workforce in the mid-1960s could have made a tidy living from his original skill set, retiring in 2000 after a final burst of Y2K project work. An MIS executive could have stayed mainframe-centric into the 1990s.

In today’s world, technology professionals and executives are confronted by technologies that change every 18 months, as well as by outsourcers and offshore competitors. IT will continue to be at the foundation of the global economy, but the future path of IT careers is unclear.

Telecommunications — Ma Bell to Wild West: The automated switchboard replaced the need for an infinite number of telephone operators in the first third of the 20th century. AT&T Corp., also known as Ma Bell, had a utility-like monopoly on phone service until its court-ordered breakup in the 1980s.

AT&T brimmed with technological advances. (Bell Labs was one of the top five research-and-development centers in the country for nearly 50 years.) But the corporation introduced new innovations at its own (slow) pace.

Today, the telecommunications industry is recovering from the aftermath of the dot-com era, and most major vendors are shadows of their former selves. Additionally, the dawning of the Voice over Internet Protocol (VOIP) era signifies a paradigm shift in technology, service delivery and even business models. Suddenly, Internet players such as eBay, Yahoo and Google are potential competitors for telecommunications providers and even corporate telecom departments.