Of course there are benefits. Most journals do not pay for reviewing. But if you intend to seek a career in academia, journal reviewing is beneficial to you in that you cultivate a good reputation for yourself among the editors. Aside from the direct benefits to you, it's also an important service to the field, and thus you must do it. If you are submitting papers for publication, and thus taking up other reviewers' time, then it frankly would be selfish not to contribute some of your time to 'give back' to the field by reviewing. Finally, while many may disagree on this, I find journal reviewing fun (after all, the reason I got into this field is because it is interesting to me) and that makes it inherently worthwhile for me.

As a rule of thumb, early in your career, I would recommend never turning down a review request if it is within your ability (i.e. within an area you understand) and from a reputable journal or editor. At later stages, when people have more demands on their time, there are legitimate reasons to decline (for example, if someone knows that she's so busy she won't be able to finish the review in the amount of time the journal wants; or if she has already done one or more reviews for that same journal in a short period of time). But as an early-career scientist I think it is absolutely important to review papers every time you have the chance.

Of course there are benefits. Most journals do not pay for reviewing. But if you intend to seek a career in academia, journal reviewing is beneficial to you in that you cultivate a good reputation for yourself among the editors. Aside from the direct benefits to you, it's also an important service to the field, and thus you must do it. If you are submitting papers for publication, and thus taking up other reviewers' time, then it frankly would be selfish not to contribute some of your time to 'give back' to the field by reviewing. Finally, while many may disagree on this, I find journal reviewing fun (after all, the reason I got into this field is because it is interesting to me) and that makes it inherently worthwhile for me.

As a rule of thumb, early in your career, I would recommend never turning down a review request if it is within your ability (i.e. within an area you understand) and from a reputable journal or editor. At later stages, when people have more demands on their time, there are legitimate reasons to decline (for example, if someone knows that she's so busy she won't be able to finish the review in the amount of time the journal wants; or if she has already done one or more reviews for that same journal in a short period of time). But as an early-career scientist I think it is absolutely important to review papers every time you have the chance.

Dear Nittala,

I agree with Stephen. Do not think in terms of money. If you have the capability to review a MS you must review it. You will always learn something new out of it.  Occasionally you might get fringe benefits. If you submit MS to a journal for which you have reviewed MS, you may be given benefit of publishing colour photos free of cost, etc.

So you should never miss such a chance, provided you have the capability to review a MS.  Normally one cannot review in all fields even within a same subject. The Editors also see who can review a MS on a particular topic best. Then only they request for reviewing.

Best wishes,

Subir.

Even i too find them pretty interesting and sometimes in the journals i go to archives and see the published papers and try to gain something from that work if it is in my research area. So far i have published 10 papers and will hope to publish some more and as you said sir i too think it is better to join as a reviewer. Thank you sir for your valuable information and thoughts. 

If you have published 10 papers you definitely should review whenever you have the opportunity. Many people's rule of thumb is, for every paper they submit, they try to review three. This is because a submission typically gets about three reviews (at least in my field), and thus if you are demanding the academic community to give you three reviews for each paper you submit, then you should also give back three reviews for each paper you submit.

It is highly beneficial.  I got free access to a journal for six months by reviewing a paper submitted to that journal.  Moreover, the journals are always in search of subject experts  as reviewer.  I know of an example wherein a new species was published in an international journal but the same got merged the next year.  Obviously the paper was not reviewed by an expert in the particular field.  The journal, in this case, failed to find out the proper reviewer.  The more reviewers the journals have, the more efficacy of the publication.

If I may, I also think it's important to offer services to the very field one belongs to. Unless we help with peer reviewing, the field will only become complacent.

Thank you so much to all the people who have given me suggestions. I will surely approach a journal for getting into as a reviewer in that journal.