I/We Claim:
1. Cosmetic composition comprising:
- one or more cationic polymers having a cationic charge density greater than or equal to 5 meq/g,
- one or more silicones, and
- one or more carboxylic acids selected from mandelic acid, aspartic acid and derivatives thereof such as salts, anhydrides or esters thereof.

2. Cosmetic composition according to claim 1, wherein the cationic polymer(s) has(have) a cationic charge density in the range from 5 to 6.5 meq/g.
3. Cosmetic composition according to claim 1 or 2, wherein the cationic polymer(s) is(are) chosen from:
(1) quaternized or non-quaternized vinylpyrrolidone/
dialkylaminoalkyl (meth)acrylate copolymers;
(2) polymers composed of piperazinyl units and of divalent
alkylene or hydroxyalkylene groups containing straight or branched
chains, optionally interrupted by oxygen, sulfur or nitrogen atoms or
by aromatic or heterocyclic rings, and also the oxidation and/or
quaternization products of these polymers;
(3) water-soluble polyaminoamides prepared in particular by
polycondensation of an acidic compound with a polyamine;
(4) polyaminoamide derivatives resulting from the condensation of polyalkylene-polyamines with polycarboxylic acids, followed by alkylation with difunctional agents;
(5) polymers obtained by reacting a polyalkylene-polyamine containing two primary amine groups and at least one secondary amine group with a dicarboxylic acid chosen from diglycolic acid and saturated aliphatic dicarboxylic acids having from 3 to 8 carbon atoms;
(6) alkyldiallylamine or dialkyldiallylammonium cyclopolymers;
(7) the diquaternary ammonium polycondensates containing
repeating units corresponding to the formula:

wherein,
- R10, R11, R12 and R13, which may be identical or different, represent aliphatic, alicyclic or arylaliphatic groups containing from 1 to 20 carbon atoms or lower hydroxyalkylaliphatic groups, or alternatively R10, R11, R12 and R13, together or separately, constitute, with the nitrogen atoms to which they are attached, heterocycles optionally containing a second heteroatom other than nitrogen, or alternatively R10, R11, R12 and R13 represent a linear or branched C1-C6 alkyl group substituted with a nitrile, ester, acyl or amide group or a group -CO-O-R-D or -CO-NH-R-D where R is an alkylene group and D is a quaternary ammonium group,
- A1 and B1 represent polymethylene groups containing from 2 to 20 carbon atoms, which may be linear or branched, and saturated or unsaturated, and which may contain, linked to or inserted in the main chain, one or more aromatic rings, or one or more oxygen or sulfur atoms or sulfoxide, sulfone, disulfide, amino, alkylamino, hydroxyl, quaternary ammonium, ureido, amide or ester groups, and
- X- denotes an anion derived from an inorganic or organic acid;
(8) polyquaternary ammonium polycondensates composed of units of formula (V):

- R18, R19, R20 et R21, which may be identical or different, represent a hydrogen atom or a methyl, ethyl, propyl, p-hydroxyethyl, p-hydroxypropyl or -CH2CH2(OCH2CH2)pOH group, where p is equal to 0 or to an integer between 1 and 6, with the proviso that R18, R19, R20 and R21 do not simultaneously represent a hydrogen atom,
- r and s, which may be identical or different, are integers between 1 and 6,
- q is equal to 0 or to an integer between 1 and 34,
- X denotes a halogen atom, and
- A denotes a dihalide group or preferably represents -CH2-CH2-O-CH2-CH2-;
(9) homopolymers or copolymers derived from acrylic or methacrylic acids and comprising units:
wherein,
- R22 independently denote H or CH3,
- A2 independently denote a linear or branched alkyl group of 1 to 6 carbon atoms or a hydroxyalkyl group of 1 to 4 carbon atoms,
- R23, R24 and R25, which may be identical or different, independently denote an alkyl group of 1 to 18 carbon atoms or a benzyl group,
- R26 and R27 represent a hydrogen atom or an alkyl group of 1 to 6
carbon atoms, and
- X2- denotes an anion, for example methosulphate or halide, such as
chloride or bromide;

(10) quaternary polymers of vinylpyrrolidone and of vinylimidazole;
(11) crosslinked polymers of methacryloyloxy(C1-C4)alkyltri(C1-C4)alkylammonium salts; and
(12) mixtures thereof.

4. Cosmetic composition according to any one of the preceding claims, wherein the cationic polymer(s) is(are) chosen from alkyldiallylamine or dialkyldiallylammonium cyclopolymers , preferably chosen from dialkyldiallylammonium homopolymers, better still is the diallyldimethylammonium chloride homopolymer.
5. Cosmetic composition according to any one of the preceding claims, wherein the total amount of cationic polymers having a cationic charge density greater than or equal to 5 meq/g ranges from 0.01 to 10% by weight, preferably from 0.05% to 2% by weight, and more preferably from 0.1 to 1% by weight, relative to the total weight of the composition.
6. Cosmetic composition according to any one of the preceding claims, wherein the silicone(s) is(are) selected from dimethicones (polydimethylsiloxanes).
7. Cosmetic composition according to any one of the preceding claims, wherein the silicone(s) is(are) present in a total amount ranging from 0.5% to 10% by weight, preferably from 0.75% to 5% by weight and better still from 1% to 4% by weight, relative to the total weight of the composition.
8. Cosmetic composition according to any one of the preceding claims, wherein the carboxylic acid(s) is(are) present in a total amount ranging from 0.2% to 5% by weight, preferably from 0.5% to 3% by weight and better still from 0.75% to 2% by weight relative to the total weight of the composition.
9. Cosmetic composition according to any one of the preceding claims, which further comprises one or more surfactants, preferably chosen from anionic, amphoteric or zwitterionic, and nonionic surfactants, and mixtures thereof.
10. Cosmetic composition according to claim 9, wherein the anionic surfactants are chosen from salts, in particular salts of alkali

metals, ammoniums salts, amine salts, amino alcohol salts or the salts of alkaline earth metals, of alkyl sulphates, of alkylamide sulphates, of alkyl ether sulphates, of alkylamido ether sulphates, of alkylaryl ether sulphates, of monoglyceride sulphates and mixtures thereof .
11. Cosmetic composition according to claim 9, wherein the amphoteric or zwitterionic surfactants are chosen from (C8-C20 alkyl)betaines, (C8-C20 alkyl)amido(C2-C8 alkyl)betaines, and mixtures thereof.
12. Cosmetic composition according to claim 9, wherein from the nonionic surfactants are chosen (C6-24 alkyl)polyglycosides, ethoxylated C8-C30 fatty acid esters of sorbitan, polyethoxylated C8-C30 fatty alcohols and polyoxyethylenated C 8-C30 fatty acid esters, these compounds preferably containing from 2 to 150 mol of ethylene oxide, and mixtures thereof.
13. Cosmetic composition according to any one of claims 9 to 12, wherein the total amount of surfactant(s) ranges from 0.1 % to 35% by weight, preferably from 1% to 30% by weight, better still from 5% to 20%by weight relative to the total weight of the composition.
14. Cosmetic treatment process, in particular for washing and/or conditioning keratin fibres, such as human keratin fibres, wherein a composition according to any one of the preceding claims is applied to said keratin fibres.
15. Use of a composition according to any one of claims 1 to 13 for washing and/or conditioning keratin fibres, and in particular human keratin fibres