This is the first post of a multi-part series on being an Executive in Residence (EIR). The initial post outlining the full series can be found here.

One of the first things I learned when I accepted the role of Executive in Residence at Greylock Partners was that almost no one actually knows what that means. (I can hear my father asking me now, “You’re a resident now? Like a doctor?”)

In fairness, the role is rare enough that, outside of the Silicon Valley venture community, you might never run into it. It’s almost pathologically designed to be cryptic. Not only is it rare, but it’s also designed as a short term role, not a permanent one. If that wasn’t tricky enough, it turns out that there are a few flavors of “EIR” just to add a good dose of acronym confusion to the mix.

So before discussing the details of the Executive in Residence role, let me clarify the three different types of EIR you may come in contact with. (As a side note, the following definitions and examples are certainly biased towards my recent experience at Greylock Partners.)

• Entrepreneur in Residence. The original EIR role, the Entrepreneur in Residence role is designed for entrepreneurs who are actively working on both the conception & execution of their next company. These roles are generally structured as 3-6 month engagements without compensation, but the entrepreneur is given resources & a place to work, and significant time & exposure to the investment team at the venture capital firm. The entrepreneur benefits from the constant challenge & framing of world-class investors, and a higher than average likelihood of funding from the venture capital firm. The firm, on the other hand, gets a significant degree of proprietary access and influence over the new company.

  Notable recent examples: Nir Zuk, co-founder of Palo Alto Networks (PANW, $3B+), Josh McFarland, founder of TellApart.

• Executive in Residence. Sometimes referred to as an XIR, the Executive in Residence role is designed for executives, typically CEOs, who are in between companies. These roles are typically structured as 6-12 month engagements with limited compensation (well below typical executive salaries). The executive is given an office, with an expectation that they will split their time between working with portfolio companies, helping with due diligence on potential investments, and completing their own search efforts for their next role. The executive gets a platform for broadening their strategic thinking, networking and inside access to a number of extremely promising companies, while the firm gets inexpensive support for their portfolio companies and disproportionate access to top executive talent.

  Notable recent example: Jeff Weiner, CEO of LinkedIn (LNKD, $20B+)

• “Something Else” in Residence. Behold, the age of the SEIR. In recent years, there have been a few top venture capital firms experimenting with other “in residence” roles. There have been designers, engineers, data scientists and even growth strategists in residence. The basic proposition for this role is similar to the traditional executive in residence role, with a notable tilt towards work with portfolio companies and PR to help build the reputation of the individual and the firm.

  Notable recent examples: DJ Patil, Data Scientist in Residence, Andy Johns, Growth Strategist in Residence.

There have been quite a few good blog posts on the pros & cons of the Entrepreneur in Residence role. On the other end of the spectrum, it’s probably too early to talk categorically about the plethora of new “in residence” variants as a class.

Going forward in this series, I’ll be focusing on the Executive in Residence role. My next post will attempt to answer the question: “Should I be an Executive in Residence (EIR)?“