user86: As Black, I have never played the Scandinavian Defence, nor have I ever liked the Center Game for White.  It seems like 1. e4 d5 wastes valuable time after 2. exd5 Qxd5 3. Nc3 and Black's Queen must flee, while White can comfortably develop:

The same drawback goes to White in the Center Game: 
[FEN ""]
1. e4 e5. 2. d4 exd4 3. Qxd4 Nc6

But the opening, notwithstanding, appears to be still popular, and online players have often played it against me.  Is there some redeeming virtue that I'm missing in this defence?

user13887: I'm a Candidate FIDE Master and I've tried the Scandinavian Defence, and Modern Variation, in the last 2 years. Against weaker opposition my results were very good. Black equalises easily, and quickly, and has very active pieces. The c4 move by white, taking the centre, is hardly a serious problem for the prepared player. After all, many defences concede the centre to white, only to counterattack it later. It is a concept introduced to chess 150 years ago by the Hypermodern School in chess, of which, Aron Nimzovitch was the chief exponent. Defences of this type are the French, the Pirc, the Modern Defence, the Alekhine Defence, and are all played by strong European GMs.
To say that the Scandinavian defence is inferior is laughable,but there is a small problem,in my opinion,to be honest.If you need to win on a specific game with black and face a good opponent,if as white they play very solidly,it is hard to obtain a promising position and the majority of games at higher level end up in draws. Black gets winning chances only if the players with white press too much for the win,underestimating the position.

user117: I usually play the 2...Nf6 line.  I play it because it is forcing and I can focus on one defense, and white usually isn't as prepared for it.  It gives black a lot of play and tactical choices.  It's a fun line.

user10191: Seems to me some players have a critical opinion about the Scandi mostly based on the fact that White gains time on the queen with Nc3. Actually, White only recovers the tempo "lost" on his second move (exd5). Someone even called it "theoretically inferior" based on the first few moves.  The Scandi is perfectly playable, and there are several strong GMs playing it regularly. Tiviakov, Kramnik, Ivanchuk, Karpov on his older days just to name a few, and even Carlsen has tried it out. The Scandinavian Defence - especially the 3...Qd6 variation - equalizes in almost every possible line against 1.e4. The "problem"  (if there is one), is not the irrelevant Nc3 threatens queen discussion, but the fact that it can be difficult to win with lots of games with Black. At amateur level this is hardly a problem, because most players with White doesn't have a clue about how to play against the Scandi. At higher levels, the main line is : 

e4 d5 2.exd5 Qxd5 3.Nc3 Qd6 4.d4 Nf6 5.Nf3 c6 (also a6 is played, and GM Kovalenko's aggressive Bg4). Then only 6.Ne5 puts any pressure on Black. Earlier also 6.g3 was considered strong, but it has been well neutralized by Black thanks to the efforts of GMs Tiviakov and Kontronias. 

After 6.Ne5 play goes:  6...Nbd7 and White has three main tries: 

f4 (Shirov's idea)
7.Bf4
7.Nc4

The Bf4 variation is not a problem anymore. Black equalizes quite easy. 
7.f4 and 7.Nc4 is more challenging, but Black has found ways to maintain the balance and the theory of these lines are quite heavily developed. Playing Scandi (at least on a higher level) requires knowledge of these lines, and how to handle these quite complex middlegames. It is not enough to know just the opening lines of the scandi, it also important to know these middlegames, and you will need strong endgame abilities to win (or draw) these positions - both as White and Black. This is the "problem" of the Scandinavian (and in all other openings I guess).
Wish you all best of luck playing both sides of the Scandiavian Defence. 

user103: Here are a few reasons one may take up the defense:

Despite having the Queen kicked by the Knight, the Queen is in no real danger of being trapped, its most common escape locations being to a5 and d6.
Black's pawn structure is solid, in similar ways to the Caro-Kann.
The number of lines Black needs to know are fairly limited, this makes it an easy defense to get into.
It's not played very often, so the Black player will likely have more familiarity with the positions than White.
Black is able to develop all the pieces and castle in relative safety; notable is the ability to develop with the Bishop on c8 before ...e6 is played.


86: <p>As Black, I have never played the Scandinavian Defence, nor have I ever liked the Center Game for White.  It seems like <code>1. e4 d5</code> wastes valuable time after <code>2. exd5 Qxd5 3. Nc3</code> and Black's Queen must flee, while White can comfortably develop:</p>

<p><img src="https://i.stack.imgur.com/fclis.png" width="300"></p>

<p>The same drawback goes to White in the Center Game: </p>

<pre><code>[FEN ""]
1. e4 e5. 2. d4 exd4 3. Qxd4 Nc6
</code></pre>

<p>But the opening, notwithstanding, appears to be still popular, and online players have often played it against me.  Is there some redeeming virtue that I'm missing in this defence?</p>
 13887: <p>I'm a Candidate FIDE Master and I've tried the Scandinavian Defence, and Modern Variation, in the last 2 years. Against weaker opposition my results were very good. Black equalises easily, and quickly, and has very active pieces. The c4 move by white, taking the centre, is hardly a serious problem for the prepared player. After all, many defences concede the centre to white, only to counterattack it later. It is a concept introduced to chess 150 years ago by the Hypermodern School in chess, of which, Aron Nimzovitch was the chief exponent. Defences of this type are the French, the Pirc, the Modern Defence, the Alekhine Defence, and are all played by strong European GMs.</p>

<p>To say that the Scandinavian defence is inferior is laughable,but there is a small problem,in my opinion,to be honest.If you need to win on a specific game with black and face a good opponent,if as white they play very solidly,it is hard to obtain a promising position and the majority of games at higher level end up in draws. Black gets winning chances only if the players with white press too much for the win,underestimating the position.</p>
 117: <p>I usually play the <code>2...Nf6</code> line.  I play it because it is forcing and I can focus on one defense, and white usually isn't as prepared for it.  It gives black a lot of play and tactical choices.  It's a fun line.</p>
 10191: <p>Seems to me some players have a critical opinion about the Scandi mostly based on the fact that White gains time on the queen with Nc3. Actually, White only recovers the tempo "lost" on his second move (exd5). Someone even called it "theoretically inferior" based on the first few moves.  The Scandi is perfectly playable, and there are several strong GMs playing it regularly. Tiviakov, Kramnik, Ivanchuk, Karpov on his older days just to name a few, and even Carlsen has tried it out. The Scandinavian Defence - especially the 3...Qd6 variation - equalizes in almost every possible line against 1.e4. The "problem"  (if there is one), is not the irrelevant Nc3 threatens queen discussion, but the fact that it can be difficult to win with lots of games with Black. At amateur level this is hardly a problem, because most players with White doesn't have a clue about how to play against the Scandi. At higher levels, the main line is : </p>

<ol>
<li>e4 d5 2.exd5 Qxd5 3.Nc3 Qd6 4.d4 Nf6 5.Nf3 c6 (also a6 is played, and GM Kovalenko's aggressive Bg4). Then only 6.Ne5 puts any pressure on Black. Earlier also 6.g3 was considered strong, but it has been well neutralized by Black thanks to the efforts of GMs Tiviakov and Kontronias. </li>
</ol>

<p>After 6.Ne5 play goes:  6...Nbd7 and White has three main tries: </p>

<ol start="7">
<li>f4 (Shirov's idea)
7.Bf4
7.Nc4</li>
</ol>

<p>The Bf4 variation is not a problem anymore. Black equalizes quite easy. 
7.f4 and 7.Nc4 is more challenging, but Black has found ways to maintain the balance and the theory of these lines are quite heavily developed. Playing Scandi (at least on a higher level) requires knowledge of these lines, and how to handle these quite complex middlegames. It is not enough to know just the opening lines of the scandi, it also important to know these middlegames, and you will need strong endgame abilities to win (or draw) these positions - both as White and Black. This is the "problem" of the Scandinavian (and in all other openings I guess).</p>

<p>Wish you all best of luck playing both sides of the Scandiavian Defence. </p>
 103: <p>Here are a few reasons one may take up the defense:</p>

<ul>
<li>Despite having the Queen kicked by the Knight, the Queen is in no real danger of being trapped, its most common escape locations being to a5 and d6.</li>
<li>Black's pawn structure is solid, in similar ways to the Caro-Kann.</li>
<li>The number of lines Black needs to know are fairly limited, this makes it an easy defense to get into.</li>
<li>It's not played very often, so the Black player will likely have more familiarity with the positions than White.</li>
<li>Black is able to develop all the pieces and castle in relative safety; notable is the ability to develop with the Bishop on c8 before <code>...e6</code> is played.</li>
</ul>
