diff --git a/src/actions/__tests__/config.spec.js b/src/actions/__tests__/config.spec.js
index f32f2d44..c17db99f 100644
--- a/src/actions/__tests__/config.spec.js
+++ b/src/actions/__tests__/config.spec.js
@@ -58,7 +58,17 @@ describe('config', () => {
 
   describe('validateConfig', () => {
     it('should return the config if no errors', () => {
-      const config = fromJS({ foo: 'bar', backend: { name: 'bar' }, media_folder: 'baz', collections: [{}] });
+      const collections = [{
+        name: 'posts',
+        folder: '_posts',
+        fields: [{ name: 'title', label: 'title' }],
+      }];
+      const config = fromJS({
+        foo: 'bar',
+        backend: { name: 'bar' },
+        media_folder: 'baz',
+        collections,
+      });
       expect(
         validateConfig(config)
       ).toEqual(config);
diff --git a/src/actions/config.js b/src/actions/config.js
index c290b4fe..f563fa22 100644
--- a/src/actions/config.js
+++ b/src/actions/config.js
@@ -2,6 +2,9 @@ import yaml from "js-yaml";
 import { Map, List, fromJS } from "immutable";
 import { trimStart, flow, isBoolean, get } from "lodash";
 import { authenticateUser } from "Actions/auth";
+import { formatByExtension, supportedFormats, frontmatterFormats } from "Formats/formats";
+import { selectIdentifier } from "Reducers/collections";
+import { IDENTIFIER_FIELDS } from "Constants/fieldInference";
 import * as publishModes from "Constants/publishModes";
 
 export const CONFIG_REQUEST = "CONFIG_REQUEST";
@@ -40,6 +43,38 @@ export function applyDefaults(config) {
     });
 }
 
+function validateCollection(collection) {
+  const {
+    name,
+    folder,
+    files,
+    format,
+    extension,
+    frontmatter_delimiter: delimiter,
+    fields,
+  } = collection.toJS();
+
+  if (!folder && !files) {
+    throw new Error(`Unknown collection type for collection "${name}". Collections can be either Folder based or File based.`);
+  }
+  if (format && !supportedFormats.includes(format)) {
+    throw new Error(`Unknown collection format for collection "${name}". Supported formats are ${supportedFormats.join(',')}`);
+  }
+  if (!format && extension && !formatByExtension(extension)) {
+    // Cannot infer format from extension.
+    throw new Error(`Please set a format for collection "${name}". Supported formats are ${supportedFormats.join(',')}`);
+  }
+  if (delimiter && !frontmatterFormats.includes(format)) {
+    // Cannot set custom delimiter without explicit and proper frontmatter format declaration
+    throw new Error(`Please set a proper frontmatter format for collection "${name}" to use a custom delimiter. Supported frontmatter formats are yaml-frontmatter, toml-frontmatter, and json-frontmatter.`);
+  }
+  if (folder && !selectIdentifier(collection)) {
+    // Verify that folder-type collections have an identifier field for slug creation.
+    throw new Error(`Collection "${name}" must have a field that is a valid entry identifier. Supported fields are ${IDENTIFIER_FIELDS.join(', ')}.`);
+  }
+}
+
+
 export function validateConfig(config) {
   if (!config.get('backend')) {
     throw new Error("Error in configuration file: A `backend` wasn't found. Check your config.yml file.");
@@ -70,6 +105,12 @@ export function validateConfig(config) {
   if (!List.isList(collections) || collections.isEmpty() || !collections.first()) {
     throw new Error("Error in configuration file: Your `collections` must be an array with at least one element. Check your config.yml file.");
   }
+
+  /**
+   * Validate Collections
+   */
+  config.get('collections').forEach(validateCollection);
+
   return config;
 }
 
diff --git a/src/backends/backend.js b/src/backends/backend.js
index 33a3fc28..cf1962bc 100644
--- a/src/backends/backend.js
+++ b/src/backends/backend.js
@@ -8,7 +8,8 @@ import {
   selectEntryPath,
   selectAllowNewEntries,
   selectAllowDeletion,
-  selectFolderEntryExtension
+  selectFolderEntryExtension,
+  selectIdentifier,
 } from "Reducers/collections";
 import { createEntry } from "ValueObjects/Entry";
 import { sanitizeSlug } from "Lib/urlHelper";
@@ -42,23 +43,14 @@ class LocalStorageAuthStore {
   }
 }
 
-const slugFormatter = (template = "{{slug}}", entryData, slugConfig) => {
+const slugFormatter = (collection, entryData, slugConfig) => {
+  const template = collection.get('slug') || "{{slug}}";
   const date = new Date();
 
-  const getIdentifier = (entryData) => {
-    const validIdentifierFields = ["title", "path"];
-    const identifiers = validIdentifierFields.map((field) =>
-      entryData.find((_, key) => key.toLowerCase().trim() === field)
-    );
-
-    const identifier = identifiers.find(ident => ident !== undefined);
-
-    if (identifier === undefined) {
-      throw new Error("Collection must have a field name that is a valid entry identifier");
-    }
-
-    return identifier;
-  };
+  const identifier = entryData.get(selectIdentifier(collection));
+  if (!identifier) {
+    throw new Error("Collection must have a field name that is a valid entry identifier");
+  }
 
   const slug = template.replace(/\{\{([^\}]+)\}\}/g, (_, field) => {
     switch (field) {
@@ -75,7 +67,7 @@ const slugFormatter = (template = "{{slug}}", entryData, slugConfig) => {
       case "second":
         return (`0${ date.getSeconds() }`).slice(-2);
       case "slug":
-        return getIdentifier(entryData).trim();
+        return identifier.trim();
       default:
         return entryData.get(field, "").trim();
     }
@@ -275,7 +267,7 @@ class Backend {
       if (!selectAllowNewEntries(collection)) {
         throw (new Error("Not allowed to create new entries in this collection"));
       }
-      const slug = slugFormatter(collection.get("slug"), entryDraft.getIn(["entry", "data"]), config.get("slug"));
+      const slug = slugFormatter(collection, entryDraft.getIn(["entry", "data"]), config.get("slug"));
       const path = selectEntryPath(collection, slug);
       entryObj = {
         path,
diff --git a/src/constants/fieldInference.js b/src/constants/fieldInference.js
index cb13b0ab..0811834f 100644
--- a/src/constants/fieldInference.js
+++ b/src/constants/fieldInference.js
@@ -1,6 +1,8 @@
 import React from 'react';
 
 /* eslint-disable */
+export const IDENTIFIER_FIELDS = ['title', 'path'];
+
 export const INFERABLE_FIELDS = {
   title: {
     type: 'string',
diff --git a/src/reducers/collections.js b/src/reducers/collections.js
index 3a1abaf1..d5c7288b 100644
--- a/src/reducers/collections.js
+++ b/src/reducers/collections.js
@@ -3,14 +3,13 @@ import { has, get, escapeRegExp } from 'lodash';
 import consoleError from 'Lib/consoleError';
 import { CONFIG_SUCCESS } from 'Actions/config';
 import { FILES, FOLDER } from 'Constants/collectionTypes';
-import { INFERABLE_FIELDS } from 'Constants/fieldInference';
-import { formatByExtension, formatToExtension, supportedFormats, frontmatterFormats } from 'Formats/formats';
+import { INFERABLE_FIELDS, IDENTIFIER_FIELDS } from 'Constants/fieldInference';
+import { formatToExtension } from 'Formats/formats';
 
 const collections = (state = null, action) => {
   switch (action.type) {
     case CONFIG_SUCCESS:
       const configCollections = action.payload ? action.payload.get('collections') : List();
-      configCollections.forEach(validateCollection)
       return configCollections
         .toOrderedMap()
         .map(collection => {
@@ -27,32 +26,6 @@ const collections = (state = null, action) => {
   }
 };
 
-function validateCollection(configCollection) {
-  const {
-    name,
-    folder,
-    files,
-    format,
-    extension,
-    frontmatter_delimiter: delimiter
-  } = configCollection.toJS();
-
-  if (!folder && !files) {
-    throw new Error(`Unknown collection type for collection "${name}". Collections can be either Folder based or File based.`);
-  }
-  if (format && !supportedFormats.includes(format)) {
-    throw new Error(`Unknown collection format for collection "${name}". Supported formats are ${supportedFormats.join(',')}`);
-  }
-  if (!format && extension && !formatByExtension(extension)) {
-    // Cannot infer format from extension.
-    throw new Error(`Please set a format for collection "${name}". Supported formats are ${supportedFormats.join(',')}`);
-  }
-  if (delimiter && !frontmatterFormats.includes(format)) {
-    // Cannot set custom delimiter without explicit and proper frontmatter format declaration
-    throw new Error(`Please set a proper frontmatter format for collection "${name}" to use a custom delimiter. Supported frontmatter formats are yaml-frontmatter, toml-frontmatter, and json-frontmatter.`);
-  }
-}
-
 const selectors = {
   [FOLDER]: {
     entryExtension(collection) {
@@ -120,6 +93,10 @@ export const selectListMethod = collection => selectors[collection.get('type')].
 export const selectAllowNewEntries = collection => selectors[collection.get('type')].allowNewEntries(collection);
 export const selectAllowDeletion = collection => selectors[collection.get('type')].allowDeletion(collection);
 export const selectTemplateName = (collection, slug) => selectors[collection.get('type')].templateName(collection, slug);
+export const selectIdentifier = collection => {
+  const fieldNames = collection.get('fields').map(field => field.get('name'));
+  return IDENTIFIER_FIELDS.find(id => fieldNames.find(name => name.toLowerCase().trim() === id));
+};
 export const selectInferedField = (collection, fieldName) => {
   const inferableField = INFERABLE_FIELDS[fieldName];
   const fields = collection.get('fields');