*fluent (fluence isn't a word)

"If one person is at a C1 level & the other is A1 it can be very frustrating for both."

I disagree. I'm pretty sure that I'm about a C1 in spanish and I have no problem talking to someone that's an A1 in English as long as they don't try to bite off way more than they can chew. It just means that I get to speak mostly in Spanish which is what I want anyways. Obviously I'll still correct their mistakes and try to throw some English into the conversation for their sake (especially if it's something that I've said a million times in spanish).

The frustration in my opinion comes if people are rigid on 50/50 and let the grammar corrections get in the way of the flow of the conversation. That rarely happens for me and when it starts to happen I try to encourage people to relax a little and let the conversation and language learning come more naturally. My philosophy is essentially to follow up any correction with a question regarding the topic of conversation (even if it's kind of stupid) to keep the conversation flowing. If you're A1 or A2 you're going to have to speak mostly in your native language so as to not frustrate the other person. Expectations should be set accordingly.

The key (if you're somewhat advanced at least) in my opinion isn't to be at the same level as the other person, but for both people to have a general sense of their level and to find the sweet spot of experimenting without severely slowing down the conversation.  

P.S. I'm also a big believer in talking to native speakers if at all possible.

To be fluent, you should try to talk to people.

To talk to people, you should make friends.

To make friends, you should have topics to converse in which others are interested.

To have interesting topics, you should live among people and talk to them!

I am sorry, we met a circle! but do not worry!

Pick a part of loop and keep going! you will be fluent. This is a way I have gone through and now I can talk easily.

Best wishes

I hope you don't misunderstand my previous post.  I wasn't suggesting that I refuse to speak to A1 learners.  If anything, my opinion comes from having done it & feeling that they felt that the experience didn't help them.  As Mike said, when you speak to a newcomer to English, you tend to speak a lot in their language, which is good for your learning experience & practice.  But I have found that it's a short term experience and I think that's because they see you speaking relatively fluently in their language while they mostly speak in their language as well.  Embarrassment or disappointment sets in & they become unwilling to participate further in the future.  I've tried to draw them out, to spend more time exchanging ideas in English but to no avail.

@marcell I understand pretty well your ideas; unfortunately, our languages (Spanish-Portuguese) are different in huge aspects of English, I think this is the root of our troubles, in order to improve English skills, when we tried to emulate the way that we learnt our native language. On the other hand, Mike expressed the main purpose of this web page about to give the hand for someone who needs to better his/her skills, understanding that the another person will require comprehension and overall patience, obviously this experiment can not be win and win for everyone all time(as many people believes)... Whatever, my name is Fernando, and I am from México, I am here for the same purpose, improve my English level... So if you want or someone want to practice and improve together our English level, please add me on Skype: malestrom3131 , best regards.

*do not have the patience to help others. Of course it's easiest to speak with someone who knows everything and who tries to help others, but I can only find selfish language partners. I'm not fluent ("fluency" and "fluent" are words. "Fluence" is not) in English yet, but I can understand some words in spoken English.

At the end of the day there are far more people trying to learn English than native English speakers trying to learn another language. So take advantage of whatever opportunities that you get and understand that, whether you like it or not, native English speakers have more flexibility and options so don't burn any bridges. There's one guy that I know of here who acts like a jerk to everyone (my worst experience on italki actually) and then wonders why he can't find anyone to talk to. It's not rocket science. Long story short, be a good language partner and be patient and things will fall in to place.

As for me personally, I'm in the process of trying to integrate spanish more naturally into my life, but hopefully in another year or two I'll be satisfied with my level (and be able to have it keep improving with little effort) and then I can shift my focus back to Portuguese which I've only briefly learned.