“I’m going to chat up the barmaid. I roll Persuasion – look, it’s a natural 20. I get her to come outside with me, and then I kill her and I get a free attack because she’s surprised because I rolled that natural 20.”
Summary of incident at early session run by my son
When I started playing D&D with the boxed sets, we didn’t have skills, we just had the ability scores (Strength, Intelligence, Wisdom, Dexterity, Constitution, Charisma) and saving throws (Poison/Death Ray, Magic Wands, Paralysis/Turn to Stone, Dragon Breath, Rods/Staves/Spells).

To judge how monsters/NPCs would respond, we used the reaction table. This could vary from instant hostile to instant friendly, with them more likely to wait before deciding, and if they waited we were told to take Charisma and character actions into account (although not exactly how).
If a player wanted their character wanted to look for hidden compartments or hints of traps or similar, they told me where they were going to look and how and I decided whether they would find anything as a result.
If they were trying to dodge a blade coming out of the wall or other traps, it was typically a save vs Death Ray. Trying to dodge dragon breath was obviously save vs Dragon Breath (for half damage). Trying to avoid being caught by a gorgon’s or a medusa’s gaze was save vs Turn To Stone.
The boxed sets came out in 1983 (Basic and Expert), 1984 (Companion) and 1985 (Master), and after that TSR moved onto the Gazetteers, starting with GAZ1 The Grand Duchy of Karameikos in 1987. These started to introduce skills, but they were very specific. GAZ2 The Emirates of Ylaruam (also 1987) introduced riding checks.

Riding Checks
GAZ2 The Emirates of Ylaruam p32
Roll the character’s riding rating or less on 3d6 to succeed in an action. A character’s riding rating is his [sic] dexterity modified by the following bonuses or penalties:
* Dwarf: -4
* Halfling: – 2
* Level 1-4: -1
* Level 10 + : + 1
* Military Cavalry Training: + 1
* Born in Saddle : + 2
The next appearance comes in GAZ5 The Elves of Alfheim (1988):

Due to their background, elves have a variety of skills that are neither shown in the rule books, nor related directly to combat, thieving, or magic. These are optional additions to your D&D® campaign.
GAZ5 The Elves of Alfheim p49
Beginning Skills
All beginning Alfheim elves know two skills: Tracking, and Treewalking. They also know a special clan-based skill (each clan has a different special skill), and may select one other skill. If an elf s Intelligence is 13-15, he knows one extra skill, for a total of 5; for an Intelligence of 16-17, he knows two extra skills for a total of 6; and an Intelligence of 18 gives him 3 extra skills for a total of 7.
How Skills are used
Each skill is based on one of the character’s Abilities (Strength, Intelligence, Wisdom, Dexterity, Constitution, and Charisma).
When a circumstance arises in which the DM feels the use of a character’s skill is needed, he asks the player to roll a d20 against his current score with the Ability. If the result of the d20 roll is less than or equal to the Ability, the skill use succeeds. A roll of 20 always fails, no matter how high the chance for success.
After that skills start appearing more regularly in the gazetteers, gaining more detail. For example in GAZ11 The republic of Darokin (1989):

What follows is a list of the skills available to typical Darokinian characters, with the corresponding ability the skill is based upon. … his list is by no means exclusive. Players are encouraged to think up
new skills and use them, with the DM’s approval, of course.Advocacy: Wisdom
GAZ11 The Republic of Darokin book II players’ guide, pp8-9
Animal Training: Wisdom
Appraisal: Intelligence
Armorer: Intelligence
Bargaining: Intelligence
Bargemaking: Intelligence
Barrelmaking: Intelligence
Blacksmithing: Intelligence
Bowyer: Intelligence
Brewing: Intelligence
Building: Intelligence
Cabinetmaking: Intelligence
Canvasmaking: Intelligence
Cartmaking: Intelligence
Climbing: Dexterity
Cobbler: Intelligence
Drayer: Intelligence
Drover: Intelligence
Farming: Intelligence
Finance: Intelligence
Fletching: Intelligence
Gambling: Intelligence
Gemcutting: Intelligence
Glassblowing: Dexterity
Jeweler: Intelligence
Lawyer: Intelligence
Leatherworking: Dexterity
Lumberjack: Strength
Mining: Intelligence
Navigation: Intelligence
Negotiating: Intelligence
Netmaking: Dexterity
Persuasion: Charisma
Potter: Dexterity
Riding: Dexterity
Ropemaking: Dexterity
Saddlemaking: Intelligence
Shepherd: Intelligence
Shipbuilding: Intelligence
Ship Sailing: Intelligence
Spinning: Dexterity
Stonecutting: Intelligence
Tailor: Intelligence
Toolmaking: Intelligence
Trapbuilding: Intelligence
Wagonmaking: Intelligence
Weaponsmithing: Intelligence
Weaving: Dexterity
Wheelwright: Intelligence
Woodworking: Intelligence

By the time the Rules Cyclopedia comes out (1991, which was after I went to university and my D&D days went on pause for 20+ years) these get pulled back into the core ruleset (see p81) with an even longer list of suggested skills.
A few things strike me about these skills in comparison with those in 5th edition.
- they are much more specific and extensive than the 18 skills in 5th edition, which means the situations where they would be applicable will be less frequent
- second, while they’re d20-based (except for the Ylaruam riding skill, which is 3d6), adjustments are applied to the skill score rather than the roll, and the aim is to roll BELOW the skill score
- a natural 20 is always a FAILURE!
I didn’t actually get much chance to play with skills, but it did lead to some undesirable tendencies. Since you only had a few very specific skills, there was a tendency to try to shoehorn your few skills into as many places as possible. “We need to cross this chasm. I can do canvaswork – I’m going to cut this sheet into a rope and throw it across.”
I missed 3rd and 4th editions, and only returned to D&D a year or two after 5th edition came out. I gather 3rd edition introduced the “roll d20, add modifiers to the roll and get over a target number” system, but that 3rd and 4th editions continued with “there’s a skill for everything” proliferation. One of the goals in D&D Next (ie. 5e) was to streamline things, which is why we now have the reduced set of skills to cover everything.
This avoids the “I’ve got this skill, so I’m going to work how I can make this situation fit the skill”, and everyone has some chance with the skill.
But the very presence of the mechanism encourages the muddled thinking illustrated in my opening quote – which actually happened in one of my son’s first games with his friends.
In my next post I’ll look more into the fifth edition skills, and a flash of insight brought about by a recent post by The Angry GM (due out on Monday for non-patrons).
Postscript: after sharing this post on the BECMI Facebook page, John Howard pointed me at A Brief History of Ability Checks in Dungeons and Dragons, which looks at the main rulebooks plus a couple of issues of Dragon magazine and module N5. There are a variety of different dice rolls and modifiers, but these all seem to be guidelines for making up a check on the fly rather than specific skills like above.
Also, Håvard Frosta says there was a skills system for BECMI in one of the Dragon magazines.
4th Edition was actually where they cut back on the skills. Third edition technically had 53 skills, with Knowledge split into 10 different categories and Performance split into 9. Then there were Craft and Profession, which were both entirely up to the player to define if you took ranks in it, as they applied to each type of crafting or job separately, so you could have Craft (blacksmith) and Craft (woodworking) as two separate skills. Speak Language was another skill that split up, but each point put into immediately gave you a new language, rather than each language being a separate skill that had to be built up. That was a mess of a situation, and most of the time if you were creating NPCs you’d just put ranks into the most combat relevant skills (Balance so the NPC wasn’t at a disadvantage while on grease, Concentration if they were a spellcaster so their spells couldn’t be interrupted, Hide and Move Silently for sneaky types, Listen and Spot so they could see players trying to hide, etc) and just ignore whatever skill points the NPC had left over once the important ones were filled.
4th Edition meanwhile had 17 skills, one less than 5e does. It’s got most of the same collapsed examples that 5e has, such as Stealth instead of separate Hide and Move Silently, Perception instead of separate Listen and Spot, and has the same knowledge based skills as 5e with Arcana, History, Nature, Religion, but there’s a few changes that happened. Some skills got dropped, new ones were added. I couldn’t say which list I preferred between the two, there’s some additions to 5e that I feel are underutilized and unnecessary, and others that I think were great ideas. Both lists are far, far better than 3.5’s mess though.
Interesting. Thank you Ryan