What Makes A Top Movie Star?

Ineffable screen presence, charisma, and chemistry with their scene partners.

The Hollywood studio and publicity machine can push a very good-looking performer who is cast in a major role of a big tentpole picture or pictures (Taylor Kitsch, Hayden Christensen, Sam Worthington, Emile Hirsch, Aaron Taylor-Johnson) or is beautiful, very talented, and seemingly poised (certainly presented) to be the next "It Girl" (Gretchen Mol, Rebecca Hall, Samantha Morton, Famke Janssen, Hayley Atwell) and if they lack those qualities, which are so hard to pin down and may well be born characteristics, they'll never become a major star. A combination of luck and skill in picking projects is also a pretty significant factor, but I feel it's those indescribable components of commanding the screen that count for more than anything if you want to be the next Tom Cruise or Jennifer Lawrence.

By social networking I mean the inter mingling in the acting world. Directors, producers actors often meet up at some party , some place or another, which lead to word of mouth recommendations, auditions etc.
Jennifer did audition for the right director and everything else then became history.

There are different styles of acting and some people prefer one style to another. My girlfriend and I both work in entertainment, are both artists, and we both watch a lot of films and see a lot of plays. I tend to prefer watching actors who completely lose themselves in roles, like Dina Meyer or Lea Thompson. My girlfriend wants to see actors who are completely natural on screen, even if that means playing what seems like themselves, like Tom Hanks or Matthew McConaughey.

There are brilliant actors who are natural and believable in every role they play, but don't necessarily show a lot of range. Probably part of why we have fewer long-career "movie stars" like Humphrey Bogart or Audrey Hepburn is because we currently place emphasis on range as the more valuable talent (as you can see by all the other answers to your question that mention "not playing themselves"). Bogart was electrifying to watch and was incredibly natural, but he didn't have fake accents and hugely varying character types. Both types of acting have value, and smart casting knows which type of acting a role needs.

All true, but I am talking movies stars vs. actors.
In sports, the stars are almost always merit based, but to be a movie star, one does not necessarily have to be a great actor.
Case in point would be Marylin Monroe, who's stardom had more to do with sexuality than any thing else.
On the flip side, Forrest Whittaker is a great actor but not considered a movie star.

I disagree. The Last King of Scotland springs to mind.

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